Deep water high resolution object detection

ABSTRACT

A seabed object detection system is provided. The system can include a receiver array including streamers. The system can include a plurality of receivers coupled with the streamers. The system can include a receiver array cross-cable to couple with the first streamer and to couple with the second streamer. The receiver array cross-cable can be disposed at a first depth of a body of water. The system can include a first diverter and a second diverter coupled with the receiver array cross-cable. The system can include a source array including a first source and a second source. The source array can be coplanar to the receiver array. The system can include a source array cross-cable to couple with the first source and to couple with the second source, the source array cross-cable disposed at a second depth of the body of water.

BACKGROUND

Seismic or other operations performed on a piece of earth can identifysubterranean characteristics or features of the analyzed piece of earth.

SUMMARY

At least one aspect of the present disclosure is directed to a seabedobject detection system. The seabed object detection system can includea receiver array. The receiver array can include a first streamer and asecond streamer. The seabed object detection system can include a firstplurality of receivers coupled with the first streamer. The seabedobject detection system can include a second plurality of receiverscoupled with the second streamer. The seabed object detection system caninclude a receiver array cross-cable to couple with the first streamerand to couple with the second streamer. The receiver array cross-cablecan be disposed at a first depth of a body of water. The seabed objectdetection system can include a first diverter coupled with the receiverarray cross-cable. The seabed object detection system can include asecond diverter coupled with the receiver array cross-cable. The seabedobject detection system can include a source array comprising a firstsource and a second source. The source array can be coplanar to thereceiver array. The seabed object detection system can include a sourcearray cross-cable to couple with the first source and to couple with thesecond source. The source array cross-cable can be disposed at a seconddepth of the body of water.

At least one aspect of the present disclosure is direct to a method ofseabed object detection. The method can include providing a receiverarray. The receiver array can include a first streamer and a secondstreamer. The method can include coupling a first plurality of receiverswith the first streamer and a second plurality of receivers with thesecond streamer. The method can include coupling a receiver arraycross-cable with the first streamer and the receiver array cross-cablewith the second streamer. The method can include disposing the receiverarray cross-cable at a first depth of a body of water. The method caninclude coupling a first diverter with the receiver array cross-cableand a second diverter with the receiver array cross-cable. The methodcan include providing a source array. The source array can include afirst source and a second source. The source array can be coplanar tothe receiver array. The method can include coupling a source arraycross-cable with the first source and the source array cross-cable withthe second source. The method can include disposing the source arraycross-cable at a second depth of the body of water.

At least one aspect of the present disclosure is directed to a seabedobject detection system. The seabed object detection system can includea receiver array. The receiver array can include a first streamer. Theseabed object detection system can include a first plurality ofreceivers coupled with the first streamer. The seabed object detectionsystem can include at least one receiver of the first plurality ofreceivers to receive reflection data reflected off an object in a seabedduring a first time period and to receive reflection data reflected offan ocean surface and the object in the seabed during a second timeperiod. The first time period can be separated from the second timeperiod by a first intervening time period. The seabed object detectionsystem can include a receiver array cross-cable to couple with the firststreamer. The receiver array cross-cable can be disposed at a firstdepth of a body of water. The seabed object detection system can includea source array. The source array can include a first source. The seabedobject detection system can include a source array cross-cable to couplewith the first source. The source array cross-cable can be disposed at asecond depth of the body of water.

At least one aspect of the present disclosure is direct to a method ofseabed object detection. The method can include providing a receiverarray. The receiver array can include a first streamer. The method caninclude coupling a first plurality of receivers with the first streamer.The method can include receiving, by at least one receiver of the firstplurality of receivers, reflection data reflected off an object in aseabed during a first time period and to receive reflection datareflected off an ocean surface and the object in the seabed during asecond time period. The first time period can be separated from thesecond time period by a first intervening time period. The method caninclude coupling a receiver array cross-cable with the first streamer.The method can include disposing the receiver array cross-cable a firstdepth of a body of water. The method can include providing a sourcearray. The source array can include a first source. The method caninclude coupling a source array cross-cable with the first source. Themethod can include disposing the source array cross-cable at a seconddepth of the body of water.

BRIEF DESCRIPTION OF THE DRAWINGS

The details of one or more implementations of the subject matterdescribed in this specification are set forth in the accompanyingdrawings and the description below. Other features, aspects, andadvantages of the subject matter will become apparent from thedescription, the drawings, and the claims.

FIG. 1 illustrates a seabed object detection system according to anexample implementation.

FIG. 2 illustrates a diffraction survey according to an exampleimplementation.

FIG. 3 illustrates a seabed object detection system according to anexample implementation.

FIG. 4 illustrates a seabed object detection system according to anexample implementation.

FIG. 5 illustrates a seabed object detection system according to anexample implementation.

FIG. 6 illustrates a seabed object detection system according to anexample

FIG. 7 illustrates a method of seabed object detection according to anexample implementation.

FIG. 8 illustrates a method of seabed object detection according to anexample implementation.

Like reference numbers and designations in the various drawings indicatelike elements.

DETAILED DESCRIPTION

Reflection-based surveys as described herein can obtain informationrelating to subsurface features. An acoustic signal can reflect offsubsurface lithological formations and be acquired, analyzed andinterpreted. However, reflection-based surveys can cover a narrow areaand collect a sparse set of data, both of which are factors thatcontribute to an increased time required to complete the surveys.Additionally, small shallow objects such as boulders buried in theseabed may be difficult to precisely image due to the resolutioncapabilities of reflection-based surveys. These small objects cancomplicate or delay wind turbine, marine or ocean bottom constructionsthat are fixed to the seabed, as well as the placement of cableconnections and communication lines between these wind turbine, marineor ocean bottom constructions.

The present disclosure is directed to systems and methods for seabedobject detection. Due to the limitations of reflection-based surveys, itcan be challenging to detect small shallow objects in the seabed.Inefficiencies related to increased survey time, such as a greater riskof weather-based delays, can increase the operating cost of thesesurveys without providing an accurate map of obstacles in the seabed.Additionally, reflection-based surveys can suffer from noise issues thatinterfere with positioning of receivers and data received by thereceivers Systems and methods of the present disclosure can solve theseand other problems associated with performing a survey to detect seabedobjects.

The present disclosure is directed to systems and methods for seabedobject detection. For example, the seabed object detection system canprovide an accurate map of obstacles in the seabed. The system caninclude a receiver array including streamers. The system can include aplurality of receivers coupled with the streamers. The system caninclude a receiver array cross-cable to couple with the first streamerand to couple with the second streamer. The receiver array cross-cablecan be disposed at a first depth of a body of water. The system caninclude a first diverter and a second diverter coupled with the receiverarray cross-cable. The system can include a source array including afirst source and a second source. The source array can be coplanar tothe receiver array. The system can include a source array cross-cable tocouple with the first source and to couple with the second source, thesource array cross-cable disposed at a second depth of the body ofwater.

FIG. 1 illustrates a seabed object detection system 100 illustrative ofa marine environment in which the systems and methods of the presentdisclosure can perform a seismic survey to detect seabed objects. Theseabed object detection system 100 can include a receiver array 105. Thereceiver array 105 can include a first streamer 125. The receiver array105 can include a second streamer 130. For example, the first streamer125 may be a cable (e.g., a surface marine cable), an assembly of wires,or any component capable of connecting a receiver to a recording devicewhich may be located on a vessel 102. The first streamer 125 can coupleto a receiver array cross-cable 195. For example, the second streamer130 may be a cable (e.g., a surface marine cable), an assembly of wires,or any component capable of connecting a receiver to a recording devicewhich may be located on a vessel 102. The second streamer 130 can coupleto the receiver array cross-cable 195.

The seabed object detection system 100 can include a first plurality ofreceivers 110. The first plurality of receivers 110 can be coupled withthe first streamer 125. The first plurality of receivers 110 can bedisposed on the first streamer 125. The first plurality of receivers 110can be coupled to the first streamer 125 along a line. The firstplurality of receivers 110 can be evenly spaced along the first streamer125. The first plurality of receivers 110 can receive diffraction datadiffracted off an object in a seabed. For example, a receiver of thefirst plurality of receivers 110 may be a hydrophone or any other devicecapable of collecting seismic data. Seismic data can include reflectiondata indicating subsurface features of the seabed. Seismic data caninclude diffraction data indicating subsurface features of the seabed.The subsurface features of the seabed can include small shallow objectssuch as boulders. The small shallow objects can be between 10 cm and 100cm wide (e.g., 20 cm, 30 cm, 40 cm, 50 cm, 60 cm, 70 cm, 80 cm, 90 cm,100 cm). The small shallow objects can be greater than 100 cm. Thesesmall shallow objects can be less than 10 cm. The first plurality ofreceivers 110 can be configured to detect acoustic waves that arereflected by seabed objects. The first plurality of receivers 110 can beconfigured to detect acoustic waves that are diffracted by seabedobjects. The first plurality of receivers 110 can detect diffractiondata from edges of objects. For example, the first plurality ofreceivers 110 can detect diffraction data originating from edges oflarge objects. The large objects can have a volume of between 100 and500 cubic meters (e.g., 100 cubic meters, 200 cubic meters, 300 cubicmeters, 400 cubic meters, 500 cubic meters). The large objects can havea volume of less than 100 cubic meters. The large objects can have avolume of greater than 100 cubic meters. The large object can be ashipping container. The diffraction data can originate from corners ofthe shipping container. The first plurality of receivers 110 can detectobjects with irregular surface features. For example, the plurality ofreceivers 110 can detect objects with facets, edges, sharp boundaries,or textures. The seabed objects can be completely buried within theseabed. The seabed objects can be partially buried within the seabed.

The seabed object detection system 100 can include a second plurality ofreceivers 120. The second plurality of receivers 120 can be coupled withthe second streamer 130. The second plurality of receivers 120 can bedisposed on the second streamer 130. The second plurality of receivers120 can be coupled to the second streamer 130 along a line. The secondplurality of receivers 120 can be evenly spaced along the secondstreamer 130. The second plurality of receivers 120 can receivediffraction data diffracted off an object in a seabed. For example, areceiver of the second plurality of receivers 120 may be a hydrophone orany other device capable of collecting seismic data. Seismic data caninclude reflection data indicating subsurface features of the seabed.Seismic data can include diffraction data indicating subsurface featuresof the seabed. The subsurface features of the seabed can include smallshallow objects such as boulders. The small shallow objects can bebetween 10 cm and 100 cm wide (e.g., 20 cm, 30 cm, 40 cm, 50 cm, 60 cm,70 cm, 80 cm, 90 cm, 100 cm). The small shallow objects can be greaterthan 100 cm. These small shallow objects can be less than 10 cm. Thesecond plurality of receivers 120 can be configured to detect acousticwaves that are reflected by seabed objects. The second plurality ofreceivers 120 can be configured to detect acoustic waves that arediffracted by seabed objects. The second plurality of receivers 120 candetect diffraction data from edges of objects. For example, the secondplurality of receivers 120 can detect diffraction data originating fromedges of large objects. The large objects can have a volume of between100 and 500 cubic meters (e.g., 100 cubic meters, 200 cubic meters, 300cubic meters, 400 cubic meters, 500 cubic meters). The large objects canhave a volume of less than 100 cubic meters. The large objects can havea volume of greater than 100 cubic meters. The large object can be ashipping container. The diffraction data can originate from corners ofthe shipping container. The second plurality of receivers 120 can detectobjects with irregular surface features. For example, second pluralityof receivers 120 can detect objects with facets, edges, sharpboundaries, or textures. The seabed objects can be completely buriedwithin the seabed. The seabed objects can be partially buried within theseabed.

The seabed object detection system 100 can include a receiver arraycross-cable 195. The receiver array cross-cable 195 can couple with thefirst streamer 125. For example, the first streamer 125 can be tied tothe receiver array cross-cable 195. The receiver array cross-cable 195can couple with the first streamer 125 at a first end of the firststreamer 125. The first streamer 125 can couple to the receiver arraycross-cable 195 at multiple connections points. The receiver arraycross-cable 195 can couple with the second streamer 130. For example,the second streamer 130 can be tied to the receiver array cross-cable195. The receiver array cross-cable 195 can couple with the secondstreamer 130 at a first end of the second streamer 130. The secondstreamer 130 can couple to the receiver array cross-cable 195 atmultiple connections points. The receiver array cross-cable 195 cancouple with a source array cross-cable 197. The receiver arraycross-cable 195 can couple with a first lateral cable 180. The receiverarray cross-cable 195 can couple with the first lateral cable 180 at afirst lateral cable distal end 171. The receiver array cross-cable 195can couple with a first diverter 170. The receiver array cross-cable 195can couple with a second diverter 175. The receiver array cross-cable195 can couple with a second lateral cable 185. The receiver arraycross-cable 195 can couple with the second lateral cable 185 at a secondlateral cable distal end 181. The receiver array cross-cable 195 may bea power cable to transmit electrical power from the vessel 102 to thefirst plurality of receivers 110. The receiver array cross-cable 195 maybe a power cable to transmit electrical power from the vessel 102 to thesecond plurality of receivers 120. The receiver array cross-cable 195can be disposed at a first depth of a body of water.

The seabed object detection system 100 can include a first diverter 170.The first diverter 170 can couple with the receiver array cross-cable195. The first diverter 170 can couple with the first lateral cable 180.The first diverter 170 can couple with the first lateral cable 180 atthe first lateral cable distal end 171. The first lateral cable 180 canbe coupled with the receiver array cross-cable 195. The first diverter170 may be a diverter, a paravane or deflecting plate that redirects themotion of water past the diverter laterally to produce an amount oflateral force. The diverter can be configured to redirect flow of waterpast the diverter with respect to a direction of motion of the diverterthrough water. The diverter can include a steering device associatedwith the diverter. The steering device can redirect the flow of water tocontrol an amount of lateral force generated by the diverter.

The seabed object detection system 100 can include a second diverter175. The second diverter 175 can couple with the receiver arraycross-cable 195. The second diverter 175 can couple with the secondlateral cable 185. The second diverter 175 can couple with the secondlateral cable 185 at the first lateral cable distal end 171. The secondlateral cable 185 can be coupled with the receiver array cross-cable195. The second diverter 175 may be a diverter, a paravane or deflectingplate that redirects the motion of water past the diverter laterally toproduce an amount of lateral force. The diverter can be configured toredirect flow of water past the diverter with respect to a direction ofmotion of the diverter through water. The diverter can include asteering device associated with the diverter. The steering device canredirect the flow of water to control an amount of lateral forcegenerated by the diverter.

The seabed object detection system 100 can include a source array 127.The source array 127 can include a first source 150. For example, thefirst source 150 can generate a source shot. The first source 150 cangenerate acoustic waves. The source array 127 can generate an acousticsignal to be received by the receiver array 105. For example, the sourcearray 127 can include the first source 150 coupled to a source arraycross-cable 197. The source array 127 including the first source 150 caninclude a pattern of sources. The source array 127 can include a secondsource 155. For example, the second source 155 can generate a sourceshot. The second source 155 can generate acoustic waves. The sourcearray 127 can generate an acoustic signal to be received by the receiverarray 105. For example, the source array 127 can include the secondsource 155 coupled to the source array cross-cable 197. The source array127 including the second source 155 can include a pattern of sources.The source array 127 can be coplanar to the receiver array 105. A planeof the source array 127 can be coplanar to a plane of the receiver array105.

The seabed object detection system 100 can include a source arraycross-cable 197. The source array cross-cable 197 can couple with thefirst source 150. The source array cross-cable 197 can connect with thefirst source 150. The source array cross-cable 197 can couple with thefirst source 150 through a secondary cable. The source array cross-cable197 can couple with the second source 155. The source array cross-cable197 can connect with the second source 155. The source array cross-cable197 can couple with the second source 155 through a secondary cable. Thesource array cross-cable 197 may be a power cable to transmit electricalpower from the vessel 102 to the first source 150. The source arraycross-cable 197 may be a power cable to transmit electrical power fromthe vessel 102 to the second source 155. The source array cross-cable197 can be disposed at a second depth of the body of water.

The seabed object detection system 100 can include a first lateral cable180 to couple with a first diverter 170. The first lateral cable 180 cancouple with the source array cross-cable 197. For example, the firstlateral cable 180 may be a cable (e.g., a surface marine cable), anassembly of wires, a tether, or a rope. The first lateral cable 180 canconnect with the source array cross-cable 197. The first lateral cable180 can couple with the receiver array cross-cable 195. The receiverarray cross-cable 195 can couple with the first diverter 170. The firstlateral cable 180 can couple directly to the first diverter 170. Thefirst lateral cable 180 can couple to the first diverter 170 through asecondary cable. The first lateral cable 180 can be coupled with thereceiver array cross-cable 195 to connect with the first diverter 170.The first lateral cable 180 can be coupled with the receiver arraycross-cable 195 to connect with the first diverter 170 at the firstlateral cable distal end 171. The first lateral cable 180 may be a powercable to transmit electrical power from the vessel 102 to the firstsource 150. The first lateral cable 180 may be a power cable to transmitelectrical power from the vessel 102 to the second source 155. The firstlateral cable 180 may be a power cable to transmit electrical power fromthe vessel 102 to the first plurality of receivers 110. The firstlateral cable 180 may be a power cable to transmit electrical power fromthe vessel 102 to the second plurality of receivers 120.

The seabed object detection system 100 can include a second lateralcable 185 to couple with a second diverter 175. The second lateral cable185 can couple with the source array cross-cable 197. For example, thesecond lateral cable 185 may be a cable (e.g., a surface marine cable),an assembly of wires, a tether, or a rope. The second lateral cable 185can connect with the source array cross-cable 197. The second lateralcable 185 can couple with the receiver array cross-cable 195. Thereceiver array cross-cable 195 can couple with the second diverter 175.The second lateral cable 185 can couple directly to the second diverter175. The second lateral cable 185 can couple to the second diverter 175through a secondary cable. The second lateral cable 185 can be coupledwith the receiver array cross-cable 195 to connect with the seconddiverter 175. The second lateral cable 185 can be coupled with thereceiver array cross-cable 195 to connect with the second diverter 175at the second lateral cable distal end 181. The second lateral cable 185may be a power cable to transmit electrical power from the vessel 102 tothe first source 150. The second lateral cable 185 may be a power cableto transmit electrical power from the vessel 102 to the second source155. The second lateral cable 185 may be a power cable to transmitelectrical power from the vessel 102 to the first plurality of receivers110. The second lateral cable 185 may be a power cable to transmitelectrical power from the vessel 102 to the second plurality ofreceivers 120.

The seabed object detection system 100 can include a vessel 102. Thevessel 102 can tow the receiver array 105. The vessel 102 can tow thesource array 127. The vessel 102 can tow the source array 127 in a towdirection 101. The vessel 102 can tow the receiver array 105 in a towdirection 101. The vessel can tow the source array cross-cable 197 aheadof the receiver array cross-cable 195 relative to the tow direction 101.For example, the vessel 102 can tow the source array cross-cable 197 inthe tow direction 101. The vessel 102 can tow the receiver arraycross-cable 195 in the tow direction 101. A portion of the source arraycross-cable 197 can be ahead of a portion of the receiver arraycross-cable 195 relative to the tow direction 101. The vessel 102 can becoupled to the first lateral cable 180. The vessel 102 can be coupled tothe second lateral cable 185.

The seabed object detection system 100 can include a third streamer 135.The third streamer 135 can be located a first distance from the firststreamer 125. The third streamer 135 can be located a first distancefrom the second streamer 130. The first distance can include distancesbetween 5 meters and 30 meters. For example, the first distance can be12.5 meters. The first distance can be greater than 12.5 meters. Thefirst distance can be less than 12.5 meters. The third streamer 135 maybe a cable (e.g., a surface marine cable), an assembly of wires, or anycomponent capable of connecting a receiver to a recording device whichmay be located on the vessel 102. The receiver array 105 can include thethird streamer 135. The receiver array 105 can include multiple thirdstreamers 135. For example, the receiver array 105 can include one, two,three, or more third streamers 135.

The seabed object detection system 100 can include a fourth streamer140. The fourth streamer 140 can be located a first distance from thefirst streamer 125. The fourth streamer 140 can be located a firstdistance from the second streamer 130. The first distance can includedistances between 5 meters and 30 meters. For example, the firstdistance can be 12.5 meters. The first distance can be greater than 12.5meters. The first distance can be less than 12.5 meters. The fourthstreamer 140 may be a cable (e.g., a surface marine cable), an assemblyof wires, or any component capable of connecting a receiver to arecording device which may be located on the vessel 102. The receiverarray 105 can include the fourth streamer 140. The receiver array 105can include multiple fourth streamers 140. For example, the receiverarray 105 can include one, two, three, or more fourth streamers 140.

The seabed object detection system 100 can include a third source 160.The source array 127 can include a third source 160. The third source160 can be located between the first streamer 125 and the third streamer135. The third source 160 can be located between a first third streamer135 and a second third streamer 135. The third source 160 can generateacoustic waves to be reflected off a seabed object and received by thefirst plurality of receivers 110. The third source 160 can generateacoustic waves to be diffracted off a seabed object and received by thefirst plurality of receivers 110. The source array 127 can includemultiple third sources 160. For example, the source array 127 caninclude one, two, three, or more third sources 160. The third source 160can generate acoustic waves to be reflected off a seabed object andreceived by the second plurality of receivers 120. The third source 160can generate acoustic waves to be diffracted off a seabed object andreceived by the second plurality of receivers 120.

The seabed object detection system 100 can include a fourth source 165.The source array 127 can include a fourth source 165. The fourth source165 can be located between the second streamer 130 and the fourthstreamer 140. The fourth source 165 can be located between a firstfourth streamer 140 and a second fourth streamer 140. The fourth source165 can generate acoustic waves to be reflected off a seabed object andreceived by the first plurality of receivers 110. The fourth source 165can generate acoustic waves to be diffracted off a seabed object andreceived by the first plurality of receivers 110. The source array 127can include multiple fourth sources 165. For example, the source array127 can include one, two, three, or more fourth sources 165. The fourthsource 165 can generate acoustic waves to be reflected off a seabedobject and received by the second plurality of receivers 120. The fourthsource 165 can generate acoustic waves to be diffracted off a seabedobject and received by the second plurality of receivers 120.

The seabed object detection system 100 can include a plurality ofstreamers 115. The plurality of streamers 115 can include the firststreamer 125. The plurality of streamers 115 can include the secondstreamer 130. The plurality of streamers 115 can include one or morethird streamers 135. For example, the plurality of streamers 115 caninclude three third streamers 135. The plurality of streamers 115 caninclude one or more fourth streamers 140. For example, the plurality ofstreamers 115 can include three fourth streamers 140. The plurality ofstreamers 115 can include exactly eight streamers. A plurality ofreceivers can be disposed on the third streamer 135. A plurality ofreceivers can be disposed on the fourth streamer 140.

The seabed object detection system 100 can include a plurality ofsources. The plurality of sources can include the first source 150. Theplurality of sources can include the second source 155. The plurality ofsources can include one or more third sources 160. For example, theplurality of sources can include three third sources 160. The pluralityof sources can include one or more fourth sources 165. For example, theplurality of sources can include three fourth sources 165. The pluralityof sources can include exactly eight sources. The plurality of sourcescan generate an acoustic signal. The first plurality of receivers 110can receive reflection data reflection off an object in the seabed. Thesecond plurality of receivers 120 can receive reflection data reflectedoff an object in the seabed 220. The first source 150 can generate anacoustic signal. The first plurality of receivers 110 can receivereflection data reflection off an object in the seabed 220 and generatedby the first source 150. The second plurality of receivers 120 canreceive reflection data reflected off an object in the seabed andgenerated by the first source 150. The second source 155 can generate anacoustic signal. The first plurality of receivers 110 can receivereflection data reflection off an object in the seabed and generated bythe second source 155. The second plurality of receivers 120 can receivereflection data reflected off an object in the seabed and generated bythe second source 155.

The seabed object detection system 100 can include a power cable 190 toprovide power to the first source 150. For example, the power cable 190may be a power cable to transmit electrical power from the vessel 102 tothe first source 150. The power cable 190 may be a power cable totransmit electrical power from the source array cross-cable 197 to thefirst source 150. The power cable 190 may be multiple power cables. Theseabed object detection system 100 can include a power cable 190 toprovide power to the second source 155. For example, the power cable 190may be a power cable to transmit electrical power from the vessel 102 tothe second source 155. The power cable 190 may be a power cable totransmit electrical power from the source array cross-cable 197 to thesecond source 155.

The seabed object detection system 100 can include a power cable 190 toprovide power to the third source 160. For example, the power cable 190may be a power cable to transmit electrical power from the vessel 102 tothe third source 160. The power cable 190 may be a power cable totransmit electrical power from the source array cross-cable 197 to thethird source 160. The power cable 190 may be multiple power cables. Theseabed object detection system 100 can include a power cable 190 toprovide power to the fourth source 165. For example, the power cable 190may be a power cable to transmit electrical power from the vessel 102 tothe fourth source 165. The power cable 190 may be a power cable totransmit electrical power from the source array cross-cable 197 to thefourth source 165.

FIG. 2 illustrates a diffraction survey 200. The diffraction survey 200can include a receiver array 105 and a source array 127. The sourcearray 127 can generate a source shot 215. The source shot 215 can travelthrough a medium (e.g., sea water) and diffract off a seabed object 210.The seabed object 210 can be completed buried in the seabed 220. Theseabed object 210 can be partially buried in the seabed 220. The seabedobject 210 can include small shallow objects such as boulders. The smallshallow objects can be between 10 cm and 100 cm wide (e.g., 20 cm, 30cm, 40 cm, 50 cm, 60 cm, 70 cm, 80 cm, 90 cm, 100 cm). The small shallowobjects can be greater than 100 cm. These small shallow objects can beless than 10 cm. The waves that diffract off the seabed object 210 mayinclude diffraction data. The diffraction data may include diffractedwaves 205. The receiver array 105 can receive diffraction data. Forexample, the receiver array 105 can receive the diffracted waves 205.The first plurality of receivers 110 of the receiver array 105 canreceive diffraction data. For example, the first plurality of receivers110 can receive the diffracted waves 205. A receiver of the firstplurality of receivers 110 can receive the diffracted waves 205. Thediffraction data can include diffracted waves 205 originating from aseabed object. The diffraction data can include diffracted waves 205generated from a source shot 215. The second plurality of receivers 120of the receiver array 105 can receive diffraction data. For example, thesecond plurality of receivers 120 can receive the diffracted waves 205.A receiver of the second plurality of receivers 120 can receive thediffracted waves 205. The diffraction data can include diffracted waves205 originating from a seabed object. The diffraction data can includediffracted waves 205 generated from a source shot 215. The firstplurality of receivers 110 can detect diffraction data from edges ofobjects. For example, the first plurality of receivers 110 can detectdiffraction data originating from edges of large objects. The secondplurality of receivers 120 can detect diffraction data from edges ofobjects. For example, the second plurality of receivers 120 can detectdiffraction data originating from edges of large objects. The largeobjects can have a volume of between 100 and 500 cubic meters (e.g., 100cubic meters, 200 cubic meters, 300 cubic meters, 400 cubic meters, 500cubic meters). The large objects can have a volume of less than 100cubic meters. The large objects can have a volume of greater than 100cubic meters. The large object can be a shipping container. Thediffraction data can originate from corners of the shipping container.The first plurality of receivers 110 can detect objects with irregularsurface features. For example, the first plurality of receivers 110 candetect objects with facets, edges, sharp boundaries, or textures. Thesecond plurality of receivers 120 can detect objects with irregularsurface features. For example, the second plurality of receivers 120 candetect objects with facets, edges, sharp boundaries, or textures.

The first plurality of receivers 110 of the receiver array 105 canreceive diffraction data. The diffraction data can include diffractedwaves 205 diffracted off a seabed object that is smaller than a Fresnelzone. The Fresnel zone is an area of a reflected from which most of theenergy of a reflection is returned and arrival times of the reflectiondiffer by less than half a period from an arrival of energy propagatedfrom an energy source. Waves with such arrival times may interfereconstructively and be detected by a single arrival. Therefore, detectingreflection waves from an object smaller than the Fresnel zone may bedifficult. However, the first plurality of receivers 110 of the receiverarray 105 can detect diffracted waves from an object smaller than theFresnel zone.

The second plurality of receivers 120 of the receiver array 105 canreceive diffraction data. The diffraction data can include diffractedwaves 205 diffracted off a seabed object that is smaller than a Fresnelzone. The Fresnel zone is an area of a reflected from which most of theenergy of a reflection is returned and arrival times of the reflectiondiffer by less than half a period from an arrival of energy propagatedfrom an energy source. Waves with such arrival times may interfereconstructively and be detected by a single arrival. Therefore, detectingreflection waves from an object smaller than the Fresnel zone may bedifficult. However, the second plurality of receivers 120 of thereceiver array 105 can detect diffracted waves from an object smallerthan the Fresnel zone.

The source array 127 can generate acoustic waves. The acoustic waves caninclude a source shot 215. The acoustic waves can diffract off theobject in the seabed. The receiver array 105 can receive diffractedwaves originating from the object in the seabed. The central pair ofsources can generate acoustic waves. The first source 150 can generateacoustic waves. The second source 155 can generate acoustic waves. Areceiver of the first plurality of receivers 110 of the receiver array105 can receive the diffracted waves. A receiver disposed on the firststreamer 125 can receive the diffracted waves. A receiver disposed onthe second streamer 130 can receive the diffracted waves. A receiver ofthe second plurality of receivers 120 of the receiver array 105 canreceive the diffracted waves. A receiver disposed on the first streamer125 can receive the diffracted waves. A receiver disposed on the secondstreamer 130 can receive the diffracted waves.

FIG. 3 illustrates a seabed object detection system 100. The seabedobject detection system 100 can include a first buoy 315 coupled withthe first diverter 170. The first buoy 315 can be connected to the firstdiverter 170. The first buoy 315 can be connected to a first rod 320.The first buoy 315 can be coupled to the first rod 320. The first buoy315 can float on a sea surface 395. The sea surface 395 can include anocean surface 395. The first buoy 315 can be a floating device. Thefirst buoy 315 can be anchored. The first buoy 315 can be allowed todrift with ocean currents. The first buoy 315 can be towed by the vessel102.

The seabed object detection system 100 can include a second buoy 325coupled with the second diverter 175. The seabed object detection system100 can include a second buoy 325 coupled with the second diverter 175.The second buoy 325 can be connected to the second diverter 175. Thesecond buoy 325 can be connected to a second rod 330. The second buoy325 can be coupled to the first rod 320. The second buoy 325 can floaton a sea surface 395. The second buoy 325 can be a floating device. Thesecond buoy 325 can be anchored. The second buoy 325 can be allowed todrift with ocean currents. The second buoy 325 can be towed by thevessel 102.

The seabed object detection system 100 can include a first rod 320coupled with the first buoy 315. The seabed object detection system 100can include a first rod 320 coupled with the first diverter 170. Thefirst rod 320 can separate the first buoy 315 from the first diverter170. The first rod 320 can be coupled with the first diverter 170. Thefirst rod 320 can be connected to the first diverter 170. The first rod320 can be a structural component to separate the first buoy 315 fromthe first diverter 170.

The seabed object detection system 100 can include a second rod 330coupled with the second buoy 325. The seabed object detection system 100can include a second rod 330 coupled with the second diverter 175. Thesecond rod 330 can separate the second buoy 325 from the second diverter175. The second rod 330 can be coupled with the first diverter 170. Thesecond rod 330 can be connected to the first diverter 170. The secondrod 330 can be a structural component to separate the second buoy 325from the second diverter 175.

The seabed object detection system 100 can include a first end streamer335 of the plurality of streamers 115. The first end streamer 335 can bedisposed at a first end of the receiver array 340. The first endstreamer 335 can include a first streamer 125. The first end streamer335 can include a second streamer 130. The first end streamer 335 caninclude a third streamer 135. The first end streamer 335 can include afourth streamer 140. The first end streamer 335 can include a firstplurality of receivers 110 coupled with the first end streamer 335. Thefirst end streamer 335 can include a second plurality of receivers 110coupled with the first end streamer 335. The first end streamer 335 canbe coupled to a receiver array cross-cable 195. The first end streamer335 can be disposed a depth greater than the depth of the source array127. The first end streamer 335 can be disposed a depth less than thedepth of the source array 127.

The seabed object detection system 100 can include a second end streamer355 of the plurality of streamers 115. The second end streamer 355 canbe disposed at a second end of the receiver array 360. The second end ofthe receiver array 360 can be a distance from the first end of thereceiver array 340. The second end of the receiver array 360 can be adistance less than 100 meters from the first end of the receiver array340. For example, the second end of the receiver array 360 can be 87.5meters from the first end of the receiver array 340. The second endstreamer 355 can include a first streamer 125. The second end streamer355 can include a second streamer 130. The second end streamer 355 caninclude a third streamer 135. The second end streamer 355 can include afourth streamer 140. The second end streamer 355 can include a firstplurality of receivers 110 coupled with the second end streamer 355. Thesecond end streamer 355 can include a second plurality of receivers 110coupled with the second end streamer 355. The second end streamer 355can be coupled to a receiver array cross-cable 195. The second endstreamer 355 can be disposed a depth greater than the depth of thesource array 127. The second end streamer 355 can be disposed a depthless than the depth of the source array 127.

The seabed object detection system 100 can include a first end source345 of the plurality of sources. The first end source 345 can bedisposed at a first end of the source array 350. The first end source345 can include the first source 150. The first end source 345 caninclude the second source 155. The first end source 345 can include thethird source 160. The first end source 345 can include the fourth source165. The first end source 345 can be coupled to the source arraycross-cable 197. The first end source 345 can be disposed at a depthless than the depth of the receiver array 105. The first end source 345can be disposed at a depth greater than the depth of the receiver array105.

The seabed object detection system 100 can include a second end source365 of the plurality of sources. The second end source 365 can bedisposed at a second end of the source array 370. The second end of thesource array 370 can be a distance from the first end of the sourcearray 350. The second end of the source array 370 can be a distance fromthe first end of the source array 350. The second end of the sourcearray 370 can be a distance less than 100 meters from the first end ofthe source array 350. For example, the second end of the source array370 can be less than 87.5 meters from the first end of the source array350. The second end source 365 can include the first source 150. Thesecond end source 365 can include the second source 155. The second endsource 365 can include the third source 160. The second end source 365can include the fourth source 165. The second end source 365 can becoupled to the source array cross-cable 197. The second end source 365can be disposed at a depth less than the depth of the receiver array105. The second end source 365 can be disposed at a depth greater thanthe depth of the receiver array 105.

The seabed object detection system 100 can include the receiver arraycross-cable 195 disposed at a first depth 375. The seabed objectdetection system 100 can include the receiver array cross-cable 195disposed at a first depth 375 greater than six meters below a seasurface 395. The seabed object detection system 100 can include thereceiver array cross-cable 195 disposed at a first depth 375 less thansix meters below a sea surface 395. The seabed object detection system100 can include the receiver array cross-cable 195 disposed at a firstdepth 375 equal to six meters below a sea surface 395. The receiverarray cross-cable 195 can be disposed at a depth greater than the depthof the source array cross-cable 197. The receiver array cross-cable 195can be disposed at a depth less than the depth of the source arraycross-cable 197. The receiver array cross-cable 195 can be disposed at adepth above the seabed.

The seabed object detection system 100 can include the source arraycross-cable 197 disposed at a second depth 380. The seabed objectdetection system 100 can include the source array cross-cable 197disposed at a second depth 380 greater than four meters below the seasurface 395. The seabed object detection system 100 can include thesource array cross-cable 197 disposed at a second depth 380 less thanfour meters below the sea surface 395. The seabed object detectionsystem 100 can include the source array cross-cable 197 disposed at asecond depth 380 equal to four meters below the sea surface 395. Thesource array cross-cable 197 can be disposed at a depth greater than thedepth of the receiver array cross-cable 195. The source arraycross-cable 197 can be disposed at a depth less than the depth of thereceiver array cross-cable 195. The source array cross-cable 197 can bedisposed at a depth above the seabed.

The seabed object detection system 100 can include a first depthcontroller 385 to couple with the first diverter 170. The first depthcontroller 385 can maintain a depth of the receiver array 105. The firstdepth controller 385 can be coupled with the first rod 320. The firstdepth controller 385 can be connected to the first rod 320. The firstdepth controller 385 can be coupled with the first buoy 315. The firstdepth controller 385 can be connected to the first buoy 315. The firstdepth controller 385 can be connected to the vessel 102 by a power cable190. The power cable 190 can transmit electrical power from the vessel102 to the first depth controller 385.

The seabed object detection system 100 can include a second depthcontroller 390 to couple with the second diverter 175. The second depthcontroller 390 can maintain a depth of the receiver array 105. Thesecond depth controller 390 can maintain a depth of the receiver array105. The second depth controller 390 can be coupled with the first rod320. The second depth controller 390 can be connected to the first rod320. The second depth controller 390 can be coupled with the first buoy315. The second depth controller 390 can be connected to the first buoy315. The second depth controller 390 can be connected to the vessel 102by a power cable 190. The power cable 190 can transmit electrical powerfrom the vessel 102 to the second depth controller 390.

The seabed object detection system 100 can include the source array 127coplanar to the receiver array 105. For example, the source array 127can define a first plane. The first plane can be a plane in which thefirst source 150 and the second source 155 lie. The first plane can be aplane in which the first source 150 and the third source 160 lie. Thefirst plane can be a plane in which the first source 150 and the fourthsource 165 lie. The receiver array 105 can define a second plane. Thesecond plane can be a plane in which one receiver of the first pluralityof receivers 110 and one receiver of the second plurality of receivers120 lie. The second plane can be a plane in which a first receiver ofthe first plurality of receivers 110 and a second receiver of the firstplurality of receivers 110 lie. The second plane can be a plane in whicha first receiver of the second plurality of receivers 120 and a secondreceiver of the second plurality of receivers 120 lie.

FIG. 4 illustrates a seabed object detection system 100. The seabedobject detection system 100 can include a vessel 102. The vessel 102 cantow the receiver array 105. The vessel 102 can tow the source array 127.The vessel 102 can tow the source array 127 in a tow direction 101. Thevessel 102 can tow the receiver array 105 in a tow direction 101. Thevessel can tow the source array cross-cable 197 ahead of the receiverarray cross-cable 195 relative to the tow direction 101. For example,the vessel 102 can tow the source array cross-cable 197 in the towdirection 101. The vessel 102 can tow the receiver array cross-cable 195in the tow direction 101. A portion of the source array cross-cable 197can be ahead of a portion of the receiver array cross-cable 195 relativeto the tow direction 101. The vessel 102 can be coupled to the firstlateral cable 180. The vessel 102 can be coupled to the second lateralcable 185.

The seabed object detection system 100 can include a first lateral cable180. The first lateral cable 180 can include a tow rope. The seabedobject detection system 100 can include a first lateral cable 180 tocouple with a first diverter 170. The first lateral cable 180 can couplewith the source array cross-cable 197. For example, the first lateralcable 180 may be a cable (e.g., a surface marine cable), an assembly ofwires, a tether, or a rope. The first lateral cable 180 can connect withthe source array cross-cable 197. The first lateral cable 180 can couplewith the receiver array cross-cable 195. The receiver array cross-cable195 can couple with the first diverter 170. The first lateral cable 180can couple directly to the first diverter 170. The first lateral cable180 can couple to the first diverter 170 through a secondary cable. Thefirst lateral cable 180 can be coupled with the receiver arraycross-cable 195 to connect with the first diverter 170. The firstlateral cable 180 can be coupled with the receiver array cross-cable 195to connect with the first diverter 170 at the first lateral cable distalend 171. The first lateral cable 180 may be a power cable to transmitelectrical power from the vessel 102 to the first source 150. The firstlateral cable 180 may be a power cable to transmit electrical power fromthe vessel 102 to the second source 155. The first lateral cable 180 maybe a power cable to transmit electrical power from the vessel 102 to thefirst plurality of receivers 110. The first lateral cable 180 may be apower cable to transmit electrical power from the vessel 102 to thesecond plurality of receivers 120.

The seabed object detection system 100 can include a second lateralcable 185. The second lateral cable 185 can include a tow rope. Theseabed object detection system 100 can include a second lateral cable185 to couple with a second diverter 175. The second lateral cable 185can couple with the source array cross-cable 197. For example, thesecond lateral cable 185 may be a cable (e.g., a surface marine cable),an assembly of wires, a tether, or a rope. The second lateral cable 185can connect with the source array cross-cable 197. The second lateralcable 185 can couple with the receiver array cross-cable 195. Thereceiver array cross-cable 195 can couple with the second diverter 175.The second lateral cable 185 can couple directly to the second diverter175. The second lateral cable 185 can couple to the second diverter 175through a secondary cable. The second lateral cable 185 can be coupledwith the receiver array cross-cable 195 to connect with the seconddiverter 175. The second lateral cable 185 can be coupled with thereceiver array cross-cable 195 to connect with the second diverter 175at the second lateral cable distal end 181. The second lateral cable 185may be a power cable to transmit electrical power from the vessel 102 tothe first source 150. The second lateral cable 185 may be a power cableto transmit electrical power from the vessel 102 to the second source155. The second lateral cable 185 may be a power cable to transmitelectrical power from the vessel 102 to the first plurality of receivers110. The second lateral cable 185 may be a power cable to transmitelectrical power from the vessel 102 to the second plurality ofreceivers 120.

The seabed object detection system 100 can include a cross cable. Thecross cable can include a source array cross-cable 197. The source arraycross-cable 197 can couple with the first source 150. The source arraycross-cable 197 can connect with the first source 150. The source arraycross-cable 197 can couple with the first source 150 through a secondarycable. The source array cross-cable 197 can couple with the secondsource 155. The source array cross-cable 197 can connect with the secondsource 155. The source array cross-cable 197 can couple with the secondsource 155 through a secondary cable. The source array cross-cable 197may be a power cable to transmit electrical power from the vessel 102 tothe first source 150. The source array cross-cable 197 may be a powercable to transmit electrical power from the vessel 102 to the secondsource 155. The source array cross-cable 197 can be disposed at a seconddepth of the body of water.

The seabed object detection system 100 can include a streamer. Thestreamer can include a first streamer 125. The streamer can include asecond streamer 130. The receiver array cross-cable 195 can couple withthe first streamer 125. For example, the first streamer 125 can be tiedto the receiver array cross-cable 195. The receiver array cross-cable195 can couple with the first streamer 125 at a first end of the firststreamer 125. The first streamer 125 can couple to the receiver arraycross-cable 195 at multiple connections points. The receiver arraycross-cable 195 can couple with the second streamer 130. For example,the second streamer 130 can be tied to the receiver array cross-cable195. The receiver array cross-cable 195 can couple with the secondstreamer 130 at a first end of the second streamer 130. The secondstreamer 130 can couple to the receiver array cross-cable 195 atmultiple connections points. The receiver array cross-cable 195 cancouple with a source array cross-cable 197. The receiver arraycross-cable 195 can couple with a first lateral cable 180. The receiverarray cross-cable 195 can couple with the first lateral cable 180 at afirst lateral cable distal end 171. The receiver array cross-cable 195can couple with a first diverter 170. The receiver array cross-cable 195can couple with a second diverter 175. The receiver array cross-cable195 can couple with a second lateral cable 185. The receiver arraycross-cable 195 can couple with the second lateral cable 185 at a secondlateral cable distal end 181. The receiver array cross-cable 195 may bea power cable to transmit electrical power from the vessel 102 to thefirst plurality of receivers 110. The receiver array cross-cable 195 maybe a power cable to transmit electrical power from the vessel 102 to thesecond plurality of receivers 120. The receiver array cross-cable 195can be disposed at a first depth of a body of water.

The streamer can include a third streamer 135. The seabed objectdetection system 100 can include a third streamer 135. The thirdstreamer 135 can be located a first distance from the first streamer125. The third streamer 135 can be located a first distance from thesecond streamer 130. The first distance can include distances between 5meters and 30 meters. For example, the first distance can be 12.5meters. The third streamer 135 may be a cable (e.g., a surface marinecable), an assembly of wires, or any component capable of connecting areceiver to a recording device which may be located on the vessel 102.The receiver array 105 can include the third streamer 135. The receiverarray 105 can include multiple third streamers 135. For example, thereceiver array 105 can include one, two, three, or more third streamers135.

The streamer can include a fourth streamer 140. The seabed objectdetection system 100 can include a fourth streamer 140. The fourthstreamer 140 can be located a first distance from the first streamer125. The fourth streamer 140 can be located a first distance from thesecond streamer 130. The first distance can include distances between 5meters and 30 meters. For example, the first distance can be 12.5meters. The fourth streamer 140 may be a cable (e.g., a surface marinecable), an assembly of wires, or any component capable of connecting areceiver to a recording device which may be located on the vessel 102.The receiver array 105 can include the fourth streamer 140. The receiverarray 105 can include multiple fourth streamers 140. For example, thereceiver array 105 can include one, two, three, or more fourth streamers140.

The seabed object detection system 100 can include a module. The modulecan include a receiver of the first plurality of receivers 110. Theseabed object detection system 100 can include a first plurality ofreceivers 110. The first plurality of receivers 110 can be coupled withthe first streamer 125. The first plurality of receivers 110 can bedisposed on the first streamer 125. The first plurality of receivers 110can be coupled to the first streamer 125 along a line. The firstplurality of receivers 110 can be evenly spaced along the first streamer125. The first plurality of receivers 110 can receive diffraction datadiffracted off an object in a seabed. For example, a receiver of thefirst plurality of receivers 110 may be a hydrophone or any other devicecapable of collecting seismic data. Seismic data can include reflectiondata indicating subsurface features of the seabed. Seismic data caninclude diffraction data indicating subsurface features of the seabed.The subsurface features of the seabed can include small shallow objectssuch as boulders. The small shallow objects can be between 10 cm and 100cm wide (e.g., 20 cm, 30 cm, 40 cm, 50 cm, 60 cm, 70 cm, 80 cm, 90 cm,100 cm). The small shallow objects can be greater than 100 cm. Thesesmall shallow objects can be less than 10 cm. The first plurality ofreceivers 110 can be configured to detect acoustic waves that arereflected by seabed objects. The first plurality of receivers 110 can beconfigured to detect acoustic waves that are diffracted by seabedobjects. The first plurality of receivers 110 can detect diffractiondata from edges of objects. For example, the first plurality ofreceivers 110 can detect diffraction data originating from edges oflarge objects. The large objects can have a volume of between 100 and500 cubic meters (e.g., 100 cubic meters, 200 cubic meters, 300 cubicmeters, 400 cubic meters, 500 cubic meters). The large objects can havea volume of less than 100 cubic meters. The large objects can have avolume of greater than 100 cubic meters. The large object can be ashipping container. The diffraction data can originate from corners ofthe shipping container. The first plurality of receivers 110 can detectobjects with irregular surface features. For example, the firstplurality of receivers 110 can detect objects with facets, edges, sharpboundaries, or textures. The seabed objects can be completely buriedwithin the seabed. The seabed objects can be partially buried within theseabed.

The module can include a receiver of the second plurality of receivers110. The seabed object detection system 100 can include a secondplurality of receivers 120. The second plurality of receivers 120 can becoupled with the second streamer 130. The second plurality of receivers120 can be disposed on the second streamer 130. The second plurality ofreceivers 120 can be coupled to the second streamer 130 along a line.The second plurality of receivers 120 can be evenly spaced along thesecond streamer 130. The second plurality of receivers 120 can receivediffraction data diffracted off an object in a seabed. For example, areceiver of the second plurality of receivers 120 may be a hydrophone orany other device capable of collecting seismic data. Seismic data caninclude reflection data indicating subsurface features of the seabed.Seismic data can include diffraction data indicating subsurface featuresof the seabed. The subsurface features of the seabed can include smallshallow objects such as boulders. The small shallow objects can bebetween 10 cm and 100 cm wide (e.g., 20 cm, 30 cm, 40 cm, 50 cm, 60 cm,70 cm, 80 cm, 90 cm, 100 cm). The small shallow objects can be greaterthan 100 cm. These small shallow objects can be less than 10 cm. Thesecond plurality of receivers 120 can be configured to detect acousticwaves that are reflected by seabed objects. The second plurality ofreceivers 120 can be configured to detect acoustic waves that arediffracted by seabed objects. The second plurality of receivers 120 candetect diffraction data from edges of objects. For example, the secondplurality of receivers 120 can detect diffraction data originating fromedges of large objects. The large objects can have a volume of between100 and 500 cubic meters (e.g., 100 cubic meters, 200 cubic meters, 300cubic meters, 400 cubic meters, 500 cubic meters). The large objects canhave a volume of less than 100 cubic meters. The large objects can havea volume of greater than 100 cubic meters. The large object can be ashipping container. The diffraction data can originate from corners ofthe shipping container. The second plurality of receivers 120 can detectobjects with irregular surface features. For example, second pluralityof receivers 120 can detect objects with facets, edges, sharpboundaries, or textures. The seabed objects can be completely buriedwithin the seabed. The seabed objects can be partially buried within theseabed.

The seabed object detection system 100 can include a first buoy 315. Theseabed object detection system 100 can include the first buoy 315coupled with the first diverter 170. The first buoy 315 can be connectedto the first diverter 170. The first buoy 315 can be connected to afirst rod 320. The first buoy 315 can be coupled to the first rod 320.The first buoy 315 can float on a sea surface 395. The first buoy 315can be a floating device. The first buoy 315 can be anchored. The firstbuoy 315 can be allowed to drift with ocean currents. The first buoy 315can be towed by the vessel 102.

The seabed object detection system 100 can include a second buoy 325.The seabed object detection system 100 can include the second buoy 325coupled with the second diverter 175. The seabed object detection system100 can include a second buoy 325 coupled with the second diverter 175.The second buoy 325 can be connected to the second diverter 175. Thesecond buoy 325 can be connected to a second rod 330. The second buoy325 can be coupled to the first rod 320. The second buoy 325 can floaton a sea surface 395. The second buoy 325 can be a floating device. Thesecond buoy 325 can be anchored. The second buoy 325 can be allowed todrift with ocean currents. The second buoy 325 can be towed by thevessel 102.

The seabed object detection system 100 can include a relative globalpositioning system (RGPS) 405. The RGPS 405 can determine where anobject is located on earth with respect to another object's location.The RGPS 405 can determine the horizontal distances between one objectto another object. The RGPS 405 can determine the vertical distancesbetween one object to another object. The RGPS 405 can determine theoffsets between one object to another object. For example, the RGPS 405can determine the position of the first diverter 170 relative to thevessel 102. The RGPS 405 can determine the position of the seconddiverter 175 relative to the vessel 102. The RGPS 405 can determinerelative positioning between two moving objects. The RGPS 405 can beconnected to the first buoy 315. The RGPS 405 can be coupled to thefirst buoy 315. The RGPS 405 can be connected to the second buoy 325.The RGPS 405 can be coupled to the second buoy 325.

The seabed object detection system 100 can include an acoustictransducer 410. The acoustic transducer 410 can convert acoustic signalsinto electrical signals. The electrical signals may be transmitted tothe vessel 102. The acoustic transducer 410 can include a hydrophone.The acoustic transducer 410 can include a first plurality of receivers110. The acoustic transducer 410 can include a first plurality ofreceivers 110 coupled with the first streamer 125. The acoustictransducer 410 can include a second plurality of receivers 120. Theacoustic transducer 410 can include a second plurality of receivers 120coupled with the second streamer 130. The acoustic transducer 410 can bedisposed on a streamer. A plurality of acoustic transducers 410 can bedisposed on a plurality of streamers 115.

The seabed object detection system 100 can include a T-connector 415.The T-connector 415 can include a tee connector. The T-connecter 415 caninclude an electrical connect that connects three cables together. TheT-connector 415 can connect the receiver array cross-cable 195 to thereceiver array 105. The T-connector 415 can couple the receiver arraycross-cable 195 to the receiver array 105. For example, the T-connector415 can connect the receiver array cross-cable 195 to the first streamer125. The T-connector 415 can couple the receiver array cross-cable 195to the first streamer 125. For example, the T-connector 415 can connectthe receiver array cross-cable 195 to the second streamer 130. TheT-connector 415 can couple the receiver array cross-cable 195 to thesecond streamer 130. For example, the T-connector 415 can connect thereceiver array cross-cable 195 to the third streamer 135. TheT-connector 415 can couple the receiver array cross-cable 195 to thethird streamer 135. For example, the T-connector 415 can connect thereceiver array cross-cable 195 to the fourth streamer 140. TheT-connector 415 can couple the receiver array cross-cable 195 to thefourth streamer 140.

The seabed object detection system 100 can include a recovery line 420.The recovery line 420 may be a cable (e.g., a surface marine cable), anassembly of wires, or any component capable of connecting a receiver toa recording device which may be located on a vessel 102. The recoveryline 420 can connect the vessel 102 to the receiver array cross-cable195. The recovery line 420 can connect the vessel 102 to the sourcearray cross-cable 197.

The seabed object detection system 100 can include a signal cable 425.The signal cable 425 can include a power cable 190. The power cable 190can provide power to the first source 150. For example, the power cable190 may be a power cable to transmit electrical power from the vessel102 to the first source 150. The power cable 190 may be a power cable totransmit electrical power from the source array cross-cable 197 to thefirst source 150. The power cable 190 may be multiple power cables. Theseabed object detection system 100 can include a power cable 190 toprovide power to the second source 155. For example, the power cable 190may be a power cable to transmit electrical power from the vessel 102 tothe second source 155. The power cable 190 may be a power cable totransmit electrical power from the source array cross-cable 197 to thesecond source 155.

The seabed object detection system 100 can include a power cable 190 toprovide power to the third source 160. For example, the power cable 190may be a power cable to transmit electrical power from the vessel 102 tothe third source 160. The power cable 190 may be a power cable totransmit electrical power from the source array cross-cable 197 to thethird source 160. The power cable 190 may be multiple power cables. Theseabed object detection system 100 can include a power cable 190 toprovide power to the fourth source 165. For example, the power cable 190may be a power cable to transmit electrical power from the vessel 102 tothe fourth source 165. The power cable 190 may be a power cable totransmit electrical power from the source array cross-cable 197 to thefourth source 165.

The seabed object detection system 100 can include a spur line 430. Thespur line 430 may be a cable (e.g., a surface marine cable), an assemblyof wires, or any component capable of connecting a receiver to arecording device which may be located on a vessel 102. The spur line 430can connect the first diverter 170 to the vessel 102. The spur line 430can couple the first diverter 170 to the vessel 102. The spur line 430can couple the first diverter 170 to the receiver array cross-cable 195.The spur line 430 can connect the second diverter 175 to the vessel 102.The spur line 430 can couple the second diverter 175 to the vessel 102.The spur line 430 can couple the second diverter 175 to the receiverarray cross-cable 195.

FIG. 5 illustrates a seabed object detection system 100. The seabedobject detection system 100 can include at least one receiver of thefirst plurality of receivers 110. The at least one receiver of the firstplurality of receivers 110 can receive reflection data 505 reflected offan object in a seabed 220. The reflection data 505 can include reflectedwaves. The reflection data 505 can include a wavelet. The at least onereceiver of the first plurality of receivers 110 can receive reflectedwaves from the object in the seabed 220. The source array 127 cangenerate a source shot 215. The source shot 215 can travel through amedium (e.g., sea water) and reflect off a seabed object 210. The seabedobject 210 can be completed buried in the seabed 220. The seabed object210 can be partially buried in the seabed 220. The seabed object 210 caninclude small shallow objects such as boulders. The small shallowobjects can be between 10 cm and 100 cm wide (e.g., 20 cm, 30 cm, 40 cm,50 cm, 60 cm, 70 cm, 80 cm, 90 cm, 100 cm). The small shallow objectscan be greater than 100 cm. These small shallow objects can be less than10 cm. The waves that reflect off the seabed object 210 may includereflection data 505. The reflection data 505 may include a reflectedwave. The receiver array 105 can receive reflection data 505. Forexample, the receiver array 105 can receive the reflected wave. Areceiver of the first plurality of receivers 110 can receive thereflected wave. The reflection data 505 can include a reflected waveoriginating from a seabed object. The reflection data 505 can includethe reflected wave generated from a source shot 215. The plurality ofsources of the source array 127 can generate an acoustic signal. Thefirst plurality of receivers 110 of the receiver array 105 can receivereflection data 505 reflected off the object in the seabed 220. Thereflection data 505 can include a reflected wave. A receiver of thefirst plurality of receivers 110 can receive the reflected wavereflected off the object in the seabed 220 and generated by a source ofthe plurality of sources of the source array 127. The source array 127can be disposed at a distance 530 below the sea surface 395. Thereceiver array 105 can be disposed at a distance 535 below the seasurface 395.

The at least one receiver of the first plurality of receivers 110 canreceive reflection data 515 reflected off the ocean surface 395 and theobject in the seabed 220. The at least one receiver of the firstplurality of receivers 110 can receive reflection data 515 reflected offthe object in the seabed 220 subsequent to reflecting off the oceansurface 395. The at least one receiver of the first plurality ofreceivers 110 can receive reflected waves from the ocean surface 395.The reflection data 515 can include reflected waves. The reflection data515 can include a wavelet. The at least one receiver of the firstplurality of receivers 110 can receive reflected waves from the oceansurface 395. The source array 127 can generate a source shot 215. Thesource shot 215 can travel through a medium (e.g., sea water) andreflect off the ocean surface 395. The waves that reflect off the oceansurface 395 may include reflection data 515. The reflection data 515 mayinclude a reflected wave. The receiver array 105 can receive reflectiondata 515. For example, the receiver array 105 can receive the reflectedwave. A receiver of the first plurality of receivers 110 can receive thereflected wave. The reflection data 515 can include a reflected waveoriginating from the ocean surface 395. The reflection data 515 caninclude the reflected wave generated from a source shot 215. Theplurality of sources of the source array 127 can generate an acousticsignal. The first plurality of receivers 110 of the receiver array 105can receive reflection data 515 reflected off the ocean surface 395. Thereflection data 515 can include a reflected wave. A receiver of thefirst plurality of receivers 110 can receive the reflected wavereflected off the ocean surface 395 and generated by a source of theplurality of sources of the source array 127.

The at least one receiver of the first plurality of receivers 110 canreceive reflection data 520 reflected off a seabed 220 and reflected offthe ocean surface 395. The at least one receiver of the first pluralityof receivers 110 can receive reflection data 520 reflected off the oceansurface 395 subsequent to reflecting off the object in the seabed 220.The at least one receiver of the first plurality of receivers 110 canreceive reflected waves from the seabed 220 and the ocean surface 395.The reflection data 520 can include reflected waves. The reflection data520 can include a wavelet. The at least one receiver of the firstplurality of receivers 110 can receive reflected waves from the oceansurface 395. The source array 127 can generate a source shot 215. Thesource shot 215 can travel through a medium (e.g., sea water) andreflect off the seabed 220. The waves that reflect off the seabed 220may include reflection data 520. The waves that reflect off the seabed220 and reflect off the ocean surface 395 may include reflection data520. The reflection data 520 may include a reflected wave. The receiverarray 105 can receive reflection data 520. For example, the receiverarray 105 can receive the reflected wave. A receiver of the firstplurality of receivers 110 can receive the reflected wave. Thereflection data 520 can include a reflected wave originating from theseabed 220. The reflection data 520 can include the reflected wavegenerated from a source shot 215. The plurality of sources of the sourcearray 127 can generate an acoustic signal. The first plurality ofreceivers 110 of the receiver array 105 can receive reflection data 520reflected off the seabed 220 and reflected off the ocean surface 395.The reflection data 520 can include a reflected wave. A receiver of thefirst plurality of receivers 110 can receive the reflected wavereflected off the seabed 220 and generated by a source of the pluralityof sources of the source array 127.

The at least one receiver of the first plurality of receivers 110 canreceive reflection data 525 reflected twice off the ocean surface 395and off the object in the seabed 220. The reflection data 525 caninclude reflected waves. The reflection data 525 can include a wavelet.The at least one receiver of the first plurality of receivers 110 canreceive reflected waves from the ocean surface 395. The at least onereceiver of the first plurality of receivers 110 can receive reflectiondata 525 reflected off the ocean surface 395 subsequent to reflectingoff the object in the seabed 220 subsequent to reflecting off the oceansurface 395. The source array 127 can generate a source shot 215. Thesource shot 215 can travel through a medium (e.g., sea water) andreflect off the ocean surface 395. The reflected waves from the oceansurface 395 can reflect off the seabed 220. The reflected waves from theseabed 220 can reflect off the ocean surface 395 again. The waves thatreflect off the ocean surface 395 may include reflection data 525. Thewaves that reflect twice off the ocean surface 395 may includereflection data 525. The reflection data 525 may include a reflectedwave. The receiver array 105 can receive reflection data 525. Forexample, the receiver array 105 can receive the reflected wave. Areceiver of the first plurality of receivers 110 can receive thereflected wave. The reflection data 525 can include a reflected waveoriginating from the seabed 220. The reflection data 525 can include thereflected wave generated from a source shot 215. The plurality ofsources of the source array 127 can generate an acoustic signal. Thefirst plurality of receivers 110 of the receiver array 105 can receivereflection data 525 reflected twice off the ocean surface 395. Thereflection data 525 can include a reflected wave. A receiver of thefirst plurality of receivers 110 can receive the reflected wavereflected twice off the ocean surface 395 and generated by a source ofthe plurality of sources of the source array 127.

FIG. 6 illustrates a seabed object detection system 100. The seabedobject detection system 100 includes at least one receiver of the firstplurality of receivers 110 to receive reflection data 505 reflected offan object in a seabed during a first time period 605. The reflectiondata 505 can include reflected waves. The at least one receiver of thefirst plurality of receivers 110 can receive reflected waves from theobject in the seabed 220 during a first time period 605. The sourcearray 127 can generate a source shot 215. The source shot 215 can travelthrough a medium (e.g., sea water) and reflect off a seabed object 210.The seabed object 210 can be completed buried in the seabed 220. Theseabed object 210 can be partially buried in the seabed 220. The seabedobject 210 can include small shallow objects such as boulders. The smallshallow objects can be between 10 cm and 100 cm wide (e.g., 20 cm, 30cm, 40 cm, 50 cm, 60 cm, 70 cm, 80 cm, 90 cm, 100 cm). The small shallowobjects can be greater than 100 cm. These small shallow objects can beless than 10 cm. The waves that reflect off the seabed object 210 mayinclude reflection data 505. The reflection data 505 may include areflected wave. The receiver array 105 can receive reflection data 505during a first time period 605. For example, the receiver array 105 canreceive the reflected wave during a first time period 605. A receiver ofthe first plurality of receivers 110 can receive the reflected wave. Thereflection data 505 can include a reflected wave originating from aseabed object. The reflection data 505 can include the reflected wavegenerated from a source shot 215. The plurality of sources of the sourcearray 127 can generate an acoustic signal. The first plurality ofreceivers 110 of the receiver array 105 can receive reflection data 505reflected off the object in the seabed 220 during a first time period605. The reflection data 505 can include a reflected wave. A receiver ofthe first plurality of receivers 110 can receive the reflected wavereflected off the object in the seabed 220 and generated by a source ofthe plurality of sources of the source array 127. The first time period605 can be less than twice the difference between the distance 530 belowthe sea surface 395 and the distance 535 below the sea surface 395divided by the velocity of the wavelet. The first time period 605 can beless than 1 millisecond. The first time period 605 can be less than 5milliseconds. The first intervening time period 610 can be less than 15milliseconds. The first intervening time period 610 can be less than 10milliseconds. The first intervening time period 610 can be less than 5milliseconds. The first intervening time period 610 can be less than 1millisecond. The first intervening time period 610 can be 0milliseconds. The first intervening time period can be at least 5milliseconds.

The at least one receiver of the first plurality of receivers 110 canreceive reflection data 515 reflected off an ocean surface 395 and theobject in the seabed 220 during a second time period 615. The at leastone receiver of the first plurality of receivers 110 can receivereflected waves from the ocean surface 395 and the object in the seabed220 during a second time period 615. The reflection data 515 can includereflected waves. The at least one receiver of the first plurality ofreceivers 110 can receive reflected waves from the ocean surface 395 andthe object in the seabed 220 during a second time period 615. The sourcearray 127 can generate a source shot 215. The source shot 215 can travelthrough a medium (e.g., sea water) and reflect off the ocean surface 395and the object in the seabed 220. The waves that reflect off the oceansurface 395 and the object in the seabed 220 may include reflection data515. The reflection data 515 may include a reflected wave. The receiverarray 105 can receive reflection data 515 during a second time period615. For example, the receiver array 105 can receive the reflected waveduring a second time period 615. A receiver of the first plurality ofreceivers 110 can receive the reflected wave. The reflection data 515can include a reflected wave originating from the object in the seabed220. The reflection data 515 can include the reflected wave generatedfrom a source shot 215. The plurality of sources of the source array 127can generate an acoustic signal. The first plurality of receivers 110 ofthe receiver array 105 can receive reflection data 515 reflected off theocean surface 395 and the object in the seabed 220. The reflection data515 can include a reflected wave. A receiver of the first plurality ofreceivers 110 can receive the reflected wave reflected off the oceansurface 395 and the object in the seabed 220, and generated by a sourceof the plurality of sources of the source array 127. The second timeperiod 615 can be less than twice the difference between the distance530 below the sea surface 395 and the distance 535 below the sea surface395 divided by the velocity of the wavelet. The second time period 615can be less than 1 millisecond. The second time period 615 can be lessthan 5 milliseconds. The first intervening time period 610 can be lessthan 15 milliseconds. The first intervening time period 610 can be lessthan 10 milliseconds. The first intervening time period 610 can be lessthan 5 milliseconds. The first intervening time period 610 can be lessthan 1 millisecond. The first intervening time period 610 can be 0milliseconds. The first intervening time period can be at least 5milliseconds.

The at least one receiver of the first plurality of receivers 110 canreceive reflection data 520 reflected off the object in the seabed 220and reflected off the ocean surface 395 during a third time period 620.The at least one receiver of the first plurality of receivers 110 canreceive reflected waves from the object in the seabed 220 and the oceansurface 395 during a third time period 620. The reflection data 520 caninclude reflected waves. The at least one receiver of the firstplurality of receivers 110 can receive reflected waves from the oceansurface 395 during a third time period 620. The source array 127 cangenerate a source shot 215. The source shot 215 can travel through amedium (e.g., sea water) and reflect off the seabed 220. The waves thatreflect off the seabed 220 may include reflection data 520. The wavesthat reflect off the seabed 220 and reflect off the ocean surface 395may include reflection data 520. The reflection data 520 may include areflected wave. The receiver array 105 can receive reflection data 520during a third time period 620. For example, the receiver array 105 canreceive the reflected wave. A receiver of the first plurality ofreceivers 110 can receive the reflected wave during a third time period620. The reflection data 520 can include a reflected wave originatingfrom the seabed 220. The reflection data 520 can include the reflectedwave generated from a source shot 215. The plurality of sources of thesource array 127 can generate an acoustic signal. The first plurality ofreceivers 110 of the receiver array 105 can receive reflection data 520reflected off the seabed 220 and reflected off the ocean surface 395during a third time period 620. The reflection data 520 can include areflected wave. A receiver of the first plurality of receivers 110 canreceive the reflected wave reflected off the seabed 220 and generated bya source of the plurality of sources of the source array 127. The thirdtime period 620 can be less than twice the difference between thedistance 530 below the sea surface 395 and the distance 535 below thesea surface 395 divided by the velocity of the wavelet. The third timeperiod 620 can be less than 1 millisecond. The third time period 620 canbe less than 5 milliseconds. The second intervening time period 625 canbe less than 20 milliseconds. The second intervening time period 625 canbe less than 15 milliseconds. The second intervening time period 625 canbe less than 10 milliseconds. The second intervening time period 625 canbe less than 5 milliseconds. The second intervening time period 625 canbe less than 1 millisecond. The second intervening time period 625 canbe 0 milliseconds.

The at least one receiver of the first plurality of receivers 110 canreceive reflection data 525 reflected twice off the ocean surface 395and off the object in the seabed 220 during a fourth time period 630.The reflection data 525 can include reflected waves. The at least onereceiver of the first plurality of receivers 110 can receive reflectedwaves from the ocean surface 395 during a fourth time period 630. Thesource array 127 can generate a source shot 215. The source shot 215 cantravel through a medium (e.g., sea water) and reflect off the oceansurface 395. The reflected waves from the ocean surface 395 can reflectoff the seabed 220. The reflected waves from the seabed 220 can reflectoff the ocean surface 395 again. The waves that reflect off the oceansurface 395 may include reflection data 525. The waves that reflecttwice off the ocean surface 395 and off the seabed 220 may includereflection data 525. The reflection data 525 may include a reflectedwave. The receiver array 105 can receive reflection data 525 during afourth time period 630. For example, the receiver array 105 can receivethe reflected wave. A receiver of the first plurality of receivers 110can receive the reflected wave. The reflection data 525 can include areflected wave originating from the ocean surface 395. The reflectiondata 525 can include the reflected wave generated from a source shot215. The plurality of sources of the source array 127 can generate anacoustic signal. The first plurality of receivers 110 of the receiverarray 105 can receive reflection data 525 reflected twice off the oceansurface 395 and off the seabed 220 during a fourth time period 630. Thereflection data 525 can include a reflected wave. A receiver of thefirst plurality of receivers 110 can receive the reflected wavereflected twice off the ocean surface 395 and off the seabed 220, andgenerated by a source of the plurality of sources of the source array127. The fourth time period 630 can be less than twice the differencebetween the distance 530 below the sea surface 395 and the distance 535below the sea surface 395 divided by the velocity of the wavelet. Thefourth time period 630 can be less than 1 millisecond. The fourth timeperiod 630 can be less than 5 milliseconds. The third intervening timeperiod 635 can be less than 30 milliseconds. The third intervening timeperiod 635 can be less than 25 milliseconds. The third intervening timeperiod 635 can be less than 20 milliseconds. The third intervening timeperiod 635 can be less than 15 milliseconds. The third intervening timeperiod 635 can be less than 10 milliseconds. The third intervening timeperiod 635 can be less than 5 milliseconds. The third intervening timeperiod 635 can be 0 milliseconds.

The seabed object detection system 100 includes at least one receiver ofthe second plurality of receivers 120 to receive reflection data 505reflected off an object in a seabed during a first time period 605. Thereflection data 505 can include reflected waves. The at least onereceiver of the second plurality of receivers 120 can receive reflectedwaves from the object in the seabed 220 during a first time period 605.The source array 127 can generate a source shot 215. The source shot 215can travel through a medium (e.g., sea water) and reflect off a seabedobject 210. The seabed object 210 can be completed buried in the seabed220. The seabed object 210 can be partially buried in the seabed 220.The seabed object 210 can include small shallow objects such asboulders. The small shallow objects can be between 10 cm and 100 cm wide(e.g., 20 cm, 30 cm, 40 cm, 50 cm, 60 cm, 70 cm, 80 cm, 90 cm, 100 cm).The small shallow objects can be greater than 100 cm. These smallshallow objects can be less than 10 cm. The waves that reflect off theseabed object 210 may include reflection data 505. The reflection data505 may include a reflected wave. The receiver array 105 can receivereflection data 505 during a first time period 605. For example, thereceiver array 105 can receive the reflected wave during a first timeperiod 605. A receiver of the second plurality of receivers 120 canreceive the reflected wave. The reflection data 505 can include areflected wave originating from a seabed object. The reflection data 505can include the reflected wave generated from a source shot 215. Theplurality of sources of the source array 127 can generate an acousticsignal. The second plurality of receivers 120 of the receiver array 105can receive reflection data 505 reflected off the object in the seabed220 during a first time period 605. The reflection data 505 can includea reflected wave. A receiver of the second plurality of receivers 120can receive the reflected wave reflected off the object in the seabed220 and generated by a source of the plurality of sources of the sourcearray 127. The first time period 605 can be less than twice thedifference between the distance 530 below the sea surface 395 and thedistance 535 below the sea surface 395 divided by the velocity of thewavelet. The first time period 605 can be less than 1 millisecond. Thefirst time period 605 can be less than 5 milliseconds. The firstintervening time period 610 can be less than 15 milliseconds. The firstintervening time period 610 can be less than 10 milliseconds. The firstintervening time period 610 can be less than 5 milliseconds. The firstintervening time period 610 can be less than 1 millisecond. The firstintervening time period 610 can be 0 milliseconds. The first interveningtime period can be at least 5 milliseconds.

The at least one receiver of the second plurality of receivers 120 canreceive reflection data 515 reflected off an ocean surface 395 and theobject in the seabed 220 during a second time period 615. The at leastone receiver of the second plurality of receivers 120 can receivereflected waves from the ocean surface 395 and the object in the seabed220 during a second time period 615. The reflection data 515 can includereflected waves. The at least one receiver of the second plurality ofreceivers 120 can receive reflected waves from the ocean surface 395 andthe object in the seabed 220 during a second time period 615. The sourcearray 127 can generate a source shot 215. The source shot 215 can travelthrough a medium (e.g., sea water) and reflect off the ocean surface 395and the object in the seabed 220. The waves that reflect off the oceansurface 395 and the object in the seabed 220 may include reflection data515. The reflection data 515 may include a reflected wave. The receiverarray 105 can receive reflection data 515 during a second time period615. For example, the receiver array 105 can receive the reflected waveduring a second time period 615. A receiver of the second plurality ofreceivers 120 can receive the reflected wave. The reflection data 515can include a reflected wave originating from the object in the seabed220. The reflection data 515 can include the reflected wave generatedfrom a source shot 215. The plurality of sources of the source array 127can generate an acoustic signal. The second plurality of receivers 120of the receiver array 105 can receive reflection data 515 reflected offthe ocean surface 395 and the object in the seabed 220. The reflectiondata 515 can include a reflected wave. A receiver of the secondplurality of receivers 120 can receive the reflected wave reflected offthe ocean surface 395 and the object in the seabed 220, and generated bya source of the plurality of sources of the source array 127. The secondtime period 615 can be less than twice the difference between thedistance 530 below the sea surface 395 and the distance 535 below thesea surface 395 divided by the velocity of the wavelet. The second timeperiod 615 can be less than 1 millisecond. The second time period 615can be less than 5 milliseconds. The first intervening time period 610can be less than 15 milliseconds. The first intervening time period 610can be less than 10 milliseconds. The first intervening time period 610can be less than 5 milliseconds. The first intervening time period 610can be less than 1 millisecond. The first intervening time period 610can be 0 milliseconds. The first intervening time period can be at least5 milliseconds.

The at least one receiver of the second plurality of receivers 120 canreceive reflection data 520 reflected off the object in the seabed 220and reflected off the ocean surface 395 during a third time period 620.The at least one receiver of the second plurality of receivers 120 canreceive reflected waves from the object in the seabed 220 and the oceansurface 395 during a third time period 620. The reflection data 520 caninclude reflected waves. The at least one receiver of the secondplurality of receivers 120 can receive reflected waves from the oceansurface 395 during a third time period 620. The source array 127 cangenerate a source shot 215. The source shot 215 can travel through amedium (e.g., sea water) and reflect off the seabed 220. The waves thatreflect off the seabed 220 may include reflection data 520. The wavesthat reflect off the seabed 220 and reflect off the ocean surface 395may include reflection data 520. The reflection data 520 may include areflected wave. The receiver array 105 can receive reflection data 520during a third time period 620. For example, the receiver array 105 canreceive the reflected wave. A receiver of the second plurality ofreceivers 120 can receive the reflected wave during a third time period620. The reflection data 520 can include a reflected wave originatingfrom the seabed 220. The reflection data 520 can include the reflectedwave generated from a source shot 215. The plurality of sources of thesource array 127 can generate an acoustic signal. The second pluralityof receivers 120 of the receiver array 105 can receive reflection data520 reflected off the seabed 220 and reflected off the ocean surface 395during a third time period 620. The reflection data 520 can include areflected wave. A receiver of the second plurality of receivers 120 canreceive the reflected wave reflected off the seabed 220 and generated bya source of the plurality of sources of the source array 127. The thirdtime period 620 can be less than twice the difference between thedistance 530 below the sea surface 395 and the distance 535 below thesea surface 395 divided by the velocity of the wavelet. The third timeperiod 620 can be less than 1 millisecond. The third time period 620 canbe less than 5 milliseconds. The second intervening time period 625 canbe less than 20 milliseconds. The second intervening time period 625 canbe less than 15 milliseconds. The second intervening time period 625 canbe less than 10 milliseconds. The second intervening time period 625 canbe less than 5 milliseconds. The second intervening time period 625 canbe less than 1 millisecond. The second intervening time period 625 canbe 0 milliseconds.

The at least one receiver of the second plurality of receivers 120 canreceive reflection data 525 reflected twice off the ocean surface 395and off the object in the seabed 220 during a fourth time period 630.The reflection data 525 can include reflected waves. The at least onereceiver of the second plurality of receivers 120 can receive reflectedwaves from the ocean surface 395 during a fourth time period 630. Thesource array 127 can generate a source shot 215. The source shot 215 cantravel through a medium (e.g., sea water) and reflect off the oceansurface 395. The reflected waves from the ocean surface 395 can reflectoff the seabed 220. The reflected waves from the seabed 220 can reflectoff the ocean surface 395 again. The waves that reflect off the oceansurface 395 may include reflection data 525. The waves that reflecttwice off the ocean surface 395 and off the seabed 220 may includereflection data 525. The reflection data 525 may include a reflectedwave. The receiver array 105 can receive reflection data 525 during afourth time period 630. For example, the receiver array 105 can receivethe reflected wave. A receiver of the second plurality of receivers 120can receive the reflected wave. The reflection data 525 can include areflected wave originating from the ocean surface 395. The reflectiondata 525 can include the reflected wave generated from a source shot215. The plurality of sources of the source array 127 can generate anacoustic signal. The second plurality of receivers 120 of the receiverarray 105 can receive reflection data 525 reflected twice off the oceansurface 395 and off the seabed 220 during a fourth time period 630. Thereflection data 525 can include a reflected wave. A receiver of thesecond plurality of receivers 120 can receive the reflected wavereflected twice off the ocean surface 395 and off the seabed 220, andgenerated by a source of the plurality of sources of the source array127. The fourth time period 630 can be less than twice the differencebetween the distance 530 below the sea surface 395 and the distance 535below the sea surface 395 divided by the velocity of the wavelet. Thefourth time period 630 can be less than 1 millisecond. The fourth timeperiod 630 can be less than 5 milliseconds. The third intervening timeperiod 635 can be less than 30 milliseconds. The third intervening timeperiod 635 can be less than 25 milliseconds. The third intervening timeperiod 635 can be less than 20 milliseconds. The third intervening timeperiod 635 can be less than 15 milliseconds. The third intervening timeperiod 635 can be less than 10 milliseconds. The third intervening timeperiod 635 can be less than 5 milliseconds. The third intervening timeperiod 635 can be 0 milliseconds.

FIG. 7 illustrates a method of seabed object detection according to anembodiment. In brief summary, the method 700 can include providing areceiver array (BLOCK 705). The method 700 can include coupling areceiver with a streamer (BLOCK 710). The method 700 can includecoupling a receiver array cross-cable with a streamer (BLOCK 715). Themethod 700 can include disposing the receiver array cross-cable at afirst depth (BLOCK 720). The method 700 can include coupling a diverterwith the receiver array cross-cable (BLOCK 725). The method 700 caninclude providing a source array (BLOCK 730). The method 700 can includecoupling a source array cross-cable with a source (BLOCK 735). Themethod 700 can include disposing the source array cross-cable at asecond depth (BLOCK 740). The method 700 can include coupling a buoywith a diverter (BLOCK 745).

The method 700 can include providing a receiver array (BLOCK 705). Themethod can include providing the receiver array 105. The receiver array105 can include a first streamer 125. The receiver array 105 can includea second streamer 130. The method can include providing a plurality ofstreamers 115. The plurality of streamers 115 can include the firststreamer 125. The plurality of streamers 115 can include the secondstreamer 130. The plurality of streamers 115 can include exactly eightstreamers. The method can include providing a first end streamer 335 ofthe plurality of streamers 115. The method can include disposing thefirst end streamer 335 at the first end of the receiver array 340. Themethod can include providing a second end streamer 355 of the pluralityof streamers 115. The method can include disposing the second endstreamer 355 at the second end of the receiver array 360. The second endof the receiver array 360 can be a distance less than 100 meters fromthe first end of the receiver array 340. The method can include towing,by a vessel 102, the receiver array 105 in a tow direction 101. Themethod can include receiving, by the receiver array 105, diffractiondata that includes diffracted waves originating from a seabed object andgenerated from a source shot 215.

The method 700 can include coupling a receiver with a streamer (BLOCK710). The method can include coupling the first plurality of receivers110 with the first streamer 125. The method can include coupling thefirst plurality of receivers 110 with the second streamer 130. Themethod can include coupling the first plurality of receivers 110 withthe third streamer 135. The method can include coupling the firstplurality of receivers 110 with the fourth streamer 140. The method caninclude coupling the second plurality of receivers 120 with the firststreamer 125. The method can include coupling the second plurality ofreceivers 120 with the second streamer 130. The method can includecoupling the second plurality of receivers 120 with the third streamer135. The method can include coupling the second plurality of receivers120 with the fourth streamer 140.

The method 700 can include coupling a receiver array cross-cable with astreamer (BLOCK 715). The method can include coupling the receiver arraycross-cable 195 with the first streamer 125. The method can includecoupling the receiver array cross-cable 195 with the second streamer130. The method can include towing, by a vessel 102, source arraycross-cable 197 behind the receiver array cross-cable 195 relative tothe tow direction 101.

The method 700 can include disposing the receiver array cross-cable at afirst depth (BLOCK 720). The method can include disposing the receiverarray cross-cable 195 at a first depth 375 of the body of water. Themethod can include disposing the receiver array cross-cable 195 at thefirst depth 375 greater than six meters below the sea surface 395.

The method 700 can include coupling a diverter with the receiver arraycross-cable (BLOCK 725). The method can include coupling the firstdiverter 170 with the receiver array cross-cable 195. The method caninclude coupling the second diverter 175 with the receiver arraycross-cable 195. The method can include coupling a first depthcontroller 385 with the first diverter 170. The method can includecoupling a second depth controller 390 with the second diverter 175. Thesecond depth controller 390 and the first depth controller 385 canmaintain a depth of the receiver array 105.

The method 700 can include providing a source array (BLOCK 730). Themethod can include providing the source array 127. The source array 127can include the first source 150. The source array 127 can include thesecond source 155. The source array 127 can be coplanar to the receiverarray 105. The method can include providing a plurality of sources. Themethod can include providing a plurality of sources of the source array127. The plurality of sources can include the first source 150. Theplurality of sources can include the second source 155. The plurality ofsources can include the third source 160. The plurality of sources caninclude the fourth source 165. The plurality of sources can includeexactly eight sources. The method can include providing the first endsource 345 of the plurality of sources. The method can include disposingthe first end source 345 at the first end of the source array 350. Themethod can include providing the second end source 365 of the pluralityof sources. The method can include disposing the second end source 365at the second end of the source array 370. The second end source of thesource array 370 can be a distance less than 100 meters from the firstend of the source array 350. The method can include towing, by a vessel102, the source array 127 in a tow direction 101.

The method 700 can include coupling a source array cross-cable with asource (BLOCK 735). The method can include can include coupling thesource array cross-cable 197 with the first source 150. The method caninclude coupling the source array cross-cable 197 with the second source155. The method can include towing, by a vessel 102, source arraycross-cable 197 ahead of the receiver array cross-cable 195 relative tothe tow direction 101.

The method 700 can include disposing the source array cross-cable at asecond depth (BLOCK 740). The method can include disposing the sourcearray cross-cable 197 at the second depth 380. The method can includedisposing the source array cross-cable 197 at the second depth 380greater than four meters below the sea surface 395.

The method 700 can include coupling a buoy with a diverter (BLOCK 745).The method can include coupling the first buoy 315 with the firstdiverter 170. The method can include coupling the second buoy 325 withthe second diverter 175. The method can include coupling the first rod320 with the first buoy 315. The method can include coupling the firstrod 320 with the first diverter 170. The first rod 320 can separate thefirst buoy 315 from the first diverter 170. The method can includecoupling the second rod 330 with the second buoy 325. The method caninclude coupling the second rod 330 with the second diverter 175. Thesecond rod 330 can separate the second buoy 325 from the second diverter175.

FIG. 8 illustrates a method of seabed object detection according to anembodiment. In brief summary, the method 800 can include providing areceiver array (BLOCK 805). The method 800 can include coupling areceiver with a streamer (BLOCK 810). The method 800 can includereceiving reflection data (BLOCK 815). The method 800 can includecoupling a receiver array cross-cable with a streamer (BLOCK 820). Themethod 800 can include disposing the receiver array cross-cable at afirst depth (BLOCK 825). The method 800 can include providing a sourcearray (BLOCK 830). The method 800 can include coupling a source arraycross-cable with a source (BLOCK 835). The method 800 can includedisposing the source array cross-cable at a second depth (BLOCK 840).The method 800 can include receiving diffraction data (BLOCK 845).

The method 800 can include providing a receiver array (BLOCK 805). Themethod can include providing the receiver array 105. The receiver array105 can include a first streamer 125. The receiver array 105 can includea second streamer 130. The method can include providing a plurality ofstreamers 115. The plurality of streamers 115 can include the firststreamer 125. The plurality of streamers 115 can include the secondstreamer 130. The plurality of streamers 115 can include exactly eightstreamers. The method can include providing a first end streamer 335 ofthe plurality of streamers 115. The method can include disposing thefirst end streamer 335 at the first end of the receiver array 340. Themethod can include providing a second end streamer 355 of the pluralityof streamers 115. The method can include disposing the second endstreamer 355 at the second end of the receiver array 360. The second endof the receiver array 360 can be a distance less than 100 meters fromthe first end of the receiver array 340. The method can include towing,by a vessel 102, the receiver array 105 in a tow direction 101. Themethod can include receiving, by the receiver array 105, diffractiondata that includes diffracted waves originating from a seabed object andgenerated from a source shot 215.

The method 800 can include coupling a receiver with a streamer (BLOCK810). The method can include coupling the first plurality of receivers110 with the first streamer 125. The method can include coupling thefirst plurality of receivers 110 with the second streamer 130. Themethod can include coupling the first plurality of receivers 110 withthe third streamer 135. The method can include coupling the firstplurality of receivers 110 with the fourth streamer 140. The method caninclude coupling the second plurality of receivers 120 with the firststreamer 125. The method can include coupling the second plurality ofreceivers 120 with the second streamer 130. The method can includecoupling the second plurality of receivers 120 with the third streamer135. The method can include coupling the second plurality of receivers120 with the fourth streamer 140.

The method 800 can include receiving reflection data (BLOCK 815). Themethod can include receiving, by the first plurality of receivers,reflection data. The method can include receiving, by the firstplurality of receivers, reflection data reflected off an object in aseabed. The method can include receiving, by the second plurality ofreceivers, reflection data. The method can include receiving, by thesecond plurality of receivers, reflection data reflected off an objectin a seabed. The method can include receiving, by the at least onereceiver of the first plurality of receivers 110, reflection datareflected off an object in a seabed during a first time period 605. Themethod can include receiving, by the at least one receiver of the firstplurality of receivers 110, reflection data reflected off an oceansurface 395 and the object in the seabed 220 during a second time period615. The first time period 605 can be separated from the second timeperiod 615 by a first intervening time period 610. The method caninclude receiving, by the at least one receiver of the first pluralityof receivers 110, reflection data reflected off the object in the seabed220 and reflected off the ocean surface 395 during a third time period620. The third time period can be separated from the first time period605 by a second intervening time period 625. The method can includereceiving, by the at least one receiver of the first plurality ofreceivers 110, reflection data reflected twice off the ocean surface 395and reflected off the object in the seabed 220 during a fourth timeperiod 630. The fourth time period 630 can be separated from the firsttime period 605 by a third intervening time period 635.

The method can include receiving, by the at least one receiver of thesecond plurality of receivers 120, reflection data reflected off anobject in a seabed during a first time period 605. The method caninclude receiving, by the at least one receiver of the second pluralityof receivers 120, reflection data reflected off the ocean surface 395and the object in the seabed 220 during a second time period 615. Thefirst time period 605 can be separated from the second time period 615by a first intervening time period 610. The method can includereceiving, by the at least one receiver of the second plurality ofreceivers 120, reflection data reflected off the object in the seabed220 seabed and reflected off the ocean surface 395 during a third timeperiod 620. The third time period 620 can be separated from the firsttime period 605 by a second intervening time period 625. The method caninclude receiving, by the at least one receiver of the second pluralityof receivers 120, reflection data reflected twice off the ocean surface395 and off the object in the seabed 220 during a fourth time period630. The fourth time period 630 can be separated from the first timeperiod 605 by a third intervening time period 635

The method 800 can include coupling a receiver array cross-cable with astreamer (BLOCK 820). The method can include coupling the receiver arraycross-cable 195 with the first streamer 125. The method can includecoupling the receiver array cross-cable 195 with the second streamer130. The method can include towing, by a vessel 102, source arraycross-cable 197 behind the receiver array cross-cable 195 relative tothe tow direction 101.

The method 800 can include disposing the receiver array cross-cable at afirst depth (BLOCK 825). The method can include disposing the receiverarray cross-cable 195 at a first depth 375 of the body of water. Themethod can include disposing the receiver array cross-cable 195 at thefirst depth 375 greater than six meters below the sea surface 395.

The method 800 can include providing a source array (BLOCK 830). Themethod can include providing the source array 127. The source array 127can include the first source 150. The source array 127 can include thesecond source 155. The source array 127 can be coplanar to the receiverarray 105. The method can include providing a plurality of sources. Themethod can include providing a plurality of sources of the source array127. The plurality of sources can include the first source 150. Theplurality of sources can include the second source 155. The plurality ofsources can include the third source 160. The plurality of sources caninclude the fourth source 165. The plurality of sources can includeexactly eight sources. The method can include providing the first endsource 345 of the plurality of sources. The method can include disposingthe first end source 345 at the first end of the source array 350. Themethod can include providing the second end source 365 of the pluralityof sources. The method can include disposing the second end source 365at the second end of the source array 370. The second end source of thesource array 370 can be a distance less than 100 meters from the firstend of the source array 350. The method can include towing, by a vessel102, the source array 127 in a tow direction 101. The method can includecan include coupling the source array cross-cable 197 with the firstsource 150. The method can include coupling the source array cross-cable197 with the second source 155. The method can include towing, by avessel 102, source array cross-cable 197 ahead of the receiver arraycross-cable 195 relative to the tow direction 101.

The method 800 can include coupling a source array cross-cable with asource (BLOCK 835). The method can include can include coupling thesource array cross-cable 197 with the first source 150. The method caninclude coupling the source array cross-cable 197 with the second source155. The method can include towing, by a vessel 102, source arraycross-cable 197 ahead of the receiver array cross-cable 195 relative tothe tow direction 101.

The method 800 can include disposing the source array cross-cable at asecond depth (BLOCK 840). The method can include disposing the sourcearray cross-cable 197 at the second depth 380. The method can includedisposing the source array cross-cable 197 at the second depth 380greater than four meters below the sea surface 395.

The method 800 can include receiving diffraction data (BLOCK 845). Themethod can include receiving, by the first plurality of receivers 110,diffraction data. The method can include receiving, by the firstplurality of receivers 110, diffraction data diffracted off an object ina seabed. The method can include receiving, by the second plurality ofreceivers 120, diffraction data. The method can include receiving, bythe second plurality of receivers 120, diffraction data diffracted offan object in a seabed.

Embodiments of the subject matter and the operations described in thisspecification can be implemented in digital electronic circuitry, or incomputer software, firmware, or hardware, including the structuresdisclosed in this specification and their structural equivalents, or incombinations of one or more of them. The subject matter described inthis specification can be implemented as one or more computer programs,e.g., one or more circuits of computer program instructions, encoded onone or more computer storage media for execution by, or to control theoperation of, data processing apparatus. Alternatively or in addition,the program instructions can be encoded on an artificially generatedpropagated signal, e.g., a machine-generated electrical, optical, orelectromagnetic signal that is generated to encode information fortransmission to suitable receiver apparatus for execution by a dataprocessing apparatus. A computer storage medium can be, or be includedin, a computer-readable storage device, a computer-readable storagesubstrate, a random or serial access memory array or device, or acombination of one or more of them. Moreover, while a computer storagemedium is not a propagated signal, a computer storage medium can be asource or destination of computer program instructions encoded in anartificially generated propagated signal. The computer storage mediumcan also be, or be included in, one or more separate components or media(e.g., multiple CDs, disks, or other storage devices).

The operations described in this specification can be performed by adata processing apparatus on data stored on one or morecomputer-readable storage devices or received from other sources. Theterm “data processing apparatus” or “computing device” encompassesvarious apparatuses, devices, and machines for processing data,including by way of example a programmable processor, a computer, asystem on a chip, or multiple ones, or combinations of the foregoing.The apparatus can include special purpose logic circuitry, e.g., an FPGA(field programmable gate array) or an ASIC (application specificintegrated circuit). The apparatus can also include, in addition tohardware, code that creates an execution environment for the computerprogram in question, e.g., code that constitutes processor firmware, aprotocol stack, a database management system, an operating system, across-platform runtime environment, a virtual machine, or a combinationof one or more of them. The apparatus and execution environment canrealize various different computing model infrastructures, such as webservices, distributed computing and grid computing infrastructures.

A computer program (also known as a program, software, softwareapplication, script, or code) can be written in any form of programminglanguage, including compiled or interpreted languages, declarative orprocedural languages, and it can be deployed in any form, including as astand-alone program or as a circuit, component, subroutine, object, orother unit suitable for use in a computing environment. A computerprogram may, but need not, correspond to a file in a file system. Aprogram can be stored in a portion of a file that holds other programsor data (e.g., one or more scripts stored in a markup languagedocument), in a single file dedicated to the program in question, or inmultiple coordinated files (e.g., files that store one or more circuits,subprograms, or portions of code). A computer program can be deployed tobe executed on one computer or on multiple computers that are located atone site or distributed across multiple sites and interconnected by acommunication network.

Processors suitable for the execution of a computer program include, byway of example, microprocessors, and any one or more processors of adigital computer. A processor can receive instructions and data from aread only memory or a random access memory or both. The elements of acomputer are a processor for performing actions in accordance withinstructions and one or more memory devices for storing instructions anddata. A computer can include, or be operatively coupled to receive datafrom or transfer data to, or both, one or more mass storage devices forstoring data, e.g., magnetic, magneto optical disks, or optical disks. Acomputer need not have such devices. Moreover, a computer can beembedded in another device, e.g., a personal digital assistant (PDA), aGlobal Positioning System (GPS) receiver, or a portable storage device(e.g., a universal serial bus (USB) flash drive), to name just a few.Devices suitable for storing computer program instructions and datainclude all forms of non-volatile memory, media and memory devices,including by way of example semiconductor memory devices, e.g., EPROM,EEPROM, and flash memory devices; magnetic disks, e.g., internal harddisks or removable disks; magneto optical disks; and CD ROM and DVD-ROMdisks. The processor and the memory can be supplemented by, orincorporated in, special purpose logic circuitry.

To provide for interaction with a user, implementations of the subjectmatter described in this specification can be implemented on a computerhaving a display device, e.g., a CRT (cathode ray tube) or LCD (liquidcrystal display) monitor, for displaying information to the user and akeyboard and a pointing device, e.g., a mouse or a trackball, by whichthe user can provide input to the computer. Other kinds of devices canbe used to provide for interaction with a user as well; for example,feedback provided to the user can be any form of sensory feedback, e.g.,visual feedback, auditory feedback, or tactile feedback; and input fromthe user can be received in any form, including acoustic, speech, ortactile input.

The implementations described herein can be implemented in any ofnumerous ways including, for example, using hardware, software or acombination thereof. When implemented in software, the software code canbe executed on any suitable processor or collection of processors,whether provided in a single computer or distributed among multiplecomputers.

Also, a computer may have one or more input and output devices. Thesedevices can be used, among other things, to present a user interface.Examples of output devices that can be used to provide a user interfaceinclude printers or display screens for visual presentation of outputand speakers or other sound generating devices for audible presentationof output. Examples of input devices that can be used for a userinterface include keyboards, and pointing devices, such as mice, touchpads, and digitizing tablets. As another example, a computer may receiveinput information through speech recognition or in other audible format.

Such computers may be interconnected by one or more networks in anysuitable form, including a local area network or a wide area network,such as an enterprise network, and intelligent network (IN) or theInternet. Such networks may be based on any suitable technology and mayoperate according to any suitable protocol and may include wirelessnetworks, wired networks or fiber optic networks.

A computer employed to implement at least a portion of the functionalitydescribed herein may comprise a memory, one or more processing units(also referred to herein simply as “processors”), one or morecommunication interfaces, one or more display units, and one or moreuser input devices. The memory may comprise any computer-readable media,and may store computer instructions (also referred to herein as“processor-executable instructions”) for implementing the variousfunctionalities described herein. The processing unit(s) may be used toexecute the instructions. The communication interface(s) may be coupledto a wired or wireless network, bus, or other communication means andmay therefore allow the computer to transmit communications to orreceive communications from other devices. The display unit(s) may beprovided, for example, to allow a user to view various information inconnection with execution of the instructions. The user input device(s)may be provided, for example, to allow the user to make manualadjustments, make selections, enter data or various other information,or interact in any of a variety of manners with the processor duringexecution of the instructions.

The various methods or processes outlined herein may be coded assoftware that is executable on one or more processors that employ anyone of a variety of operating systems or platforms. Additionally, suchsoftware may be written using any of a number of suitable programminglanguages or programming or scripting tools, and also may be compiled asexecutable machine language code or intermediate code that is executedon a framework or virtual machine.

In this respect, various inventive concepts may be embodied as acomputer readable storage medium (or multiple computer readable storagemedia) (e.g., a computer memory, one or more floppy discs, compactdiscs, optical discs, magnetic tapes, flash memories, circuitconfigurations in Field Programmable Gate Arrays or other semiconductordevices, or other non-transitory medium or tangible computer storagemedium) encoded with one or more programs that, when executed on one ormore computers or other processors, perform methods that implement thevarious embodiments of the solution discussed above. The computerreadable medium or media can be transportable, such that the program orprograms stored thereon can be loaded onto one or more differentcomputers or other processors to implement various aspects of thepresent solution as discussed above.

The terms “program” or “software” are used herein to refer to any typeof computer code or set of computer-executable instructions that can beemployed to program a computer or other processor to implement variousaspects of embodiments as discussed above. One or more computer programsthat when executed perform methods of the present solution need notreside on a single computer or processor, but may be distributed in amodular fashion amongst a number of different computers or processors toimplement various aspects of the present solution.

Computer-executable instructions may be in many forms, such as programmodules, executed by one or more computers or other devices. Programmodules can include routines, programs, objects, components, datastructures, or other components that perform particular tasks orimplement particular abstract data types. The functionality of theprogram modules can be combined or distributed as desired in variousembodiments.

Also, data structures may be stored in computer-readable media in anysuitable form. For simplicity of illustration, data structures may beshown to have fields that are related through location in the datastructure. Such relationships may likewise be achieved by assigningstorage for the fields with locations in a computer-readable medium thatconvey relationship between the fields. However, any suitable mechanismmay be used to establish a relationship between information in fields ofa data structure, including through the use of pointers, tags or othermechanisms that establish relationship between data elements.

Any references to implementations or elements or acts of the systems andmethods herein referred to in the singular can include implementationsincluding a plurality of these elements, and any references in plural toany implementation or element or act herein can include implementationsincluding only a single element. References in the singular or pluralform are not intended to limit the presently disclosed systems ormethods, their components, acts, or elements to single or pluralconfigurations. References to any act or element being based on anyinformation, act or element may include implementations where the act orelement is based at least in part on any information, act, or element.

Any implementation disclosed herein may be combined with any otherimplementation, and references to “an implementation,” “someimplementations,” “an alternate implementation,” “variousimplementations,” “one implementation” or the like are not necessarilymutually exclusive and are intended to indicate that a particularfeature, structure, or characteristic described in connection with theimplementation may be included in at least one implementation. Suchterms as used herein are not necessarily all referring to the sameimplementation. Any implementation may be combined with any otherimplementation, inclusively or exclusively, in any manner consistentwith the aspects and implementations disclosed herein.

References to “or” may be construed as inclusive so that any termsdescribed using “or” may indicate any of a single, more than one, andall of the described terms. References to at least one of a conjunctivelist of terms may be construed as an inclusive OR to indicate any of asingle, more than one, and all of the described terms. For example, areference to “at least one of ‘A’ and ‘B’” can include only ‘A’, only‘B’, as well as both ‘A’ and ‘B’. Elements other than ‘A’ and ‘B’ canalso be included.

The systems and methods described herein may be embodied in otherspecific forms without departing from the characteristics thereof. Theforegoing implementations are illustrative rather than limiting of thedescribed systems and methods.

Where technical features in the drawings, detailed description or anyclaim are followed by reference signs, the reference signs have beenincluded to increase the intelligibility of the drawings, detaileddescription, and claims. Accordingly, neither the reference signs northeir absence have any limiting effect on the scope of any claimelements.

The systems and methods described herein may be embodied in otherspecific forms without departing from the characteristics thereof. Theforegoing implementations are illustrative rather than limiting of thedescribed systems and methods. Scope of the systems and methodsdescribed herein is thus indicated by the appended claims, rather thanthe foregoing description, and changes that come within the meaning andrange of equivalency of the claims are embraced therein.

1.-20. (canceled)
 21. A seabed object detection system, comprising: areceiver array comprising a first streamer; a first plurality ofreceivers coupled with the first streamer; at least one receiver of thefirst plurality of receivers to receive reflection data reflected off anobject in a seabed during a first time period and to receive reflectiondata reflected off an ocean surface and the object in the seabed duringa second time period, the first time period separated from the secondtime period by a first intervening time period; a receiver arraycross-cable to couple with the first streamer, the receiver arraycross-cable disposed at a first depth of a body of water; a source arraycomprising a first source; and a source array cross-cable to couple withthe first source, the source array cross-cable disposed at a seconddepth of the body of water.
 22. The seabed object detection system ofclaim 21, comprising: the at least one receiver of the first pluralityof receivers to receive reflection data reflected off the object in theseabed and reflected off the ocean surface during a third time period,the third time period separated from the first time period by a secondintervening time period.
 23. The seabed object detection system of claim21, comprising: the at least one receiver of the first plurality ofreceivers to receive reflection data reflected twice off the oceansurface and off the object in the seabed during a fourth time period,the fourth time period separated from the first time period by a thirdintervening time period.
 24. The seabed object detection system of claim21, comprising: the receiver array comprising a second streamer; asecond plurality of receivers coupled with the second streamer; and atleast one receiver of the second plurality of receivers to receivereflection data reflected off the object in the seabed during the firsttime period and to receive reflection data reflected off the oceansurface and the object in the seabed during the second time period, thefirst time period separated from the second time period by the firstintervening time period.
 25. The seabed object detection system of claim21, comprising: the receiver array comprising a second streamer; asecond plurality of receivers coupled with the second streamer; and theat least one receiver of the second plurality of receivers to receivereflection data reflected off the object in the seabed and reflected offthe ocean surface during a third time period, the third time periodseparated from the first time period by a second intervening timeperiod.
 26. The seabed object detection system of claim 21, comprising:the receiver array comprising a second streamer; a second plurality ofreceivers coupled with the second streamer; and the at least onereceiver of the second plurality of receivers to receive reflection datareflected twice off the ocean surface and off the object in the seabedduring a fourth time period, the fourth time period separated from thefirst time period by a third intervening time period.
 27. The seabedobject detection system of claim 21, comprising: the first interveningtime period at least 5 milliseconds.
 28. The seabed object detectionsystem of claim 21, comprising: the source array coplanar to thereceiver array.
 29. The seabed object detection system of claim 21,comprising: at least one receiver of the first plurality of receivers toreceive diffraction data that includes diffracted waves originating froma seabed object and generated from a source shot.
 30. The seabed objectdetection system of claim 21, comprising: a vessel configured to tow thereceiver array and the source array.
 31. A method of seabed objectdetection, comprising: providing a receiver array comprising a firststreamer; coupling a first plurality of receivers with the firststreamer; receiving, by at least one receiver of the first plurality ofreceivers, reflection data reflected off an object in a seabed during afirst time period and to receive reflection data reflected off an oceansurface and the object in the seabed during a second time period, thefirst time period separated from the second time period by a firstintervening time period; coupling a receiver array cross-cable with thefirst streamer; disposing the receiver array cross-cable a first depthof a body of water; providing a source array comprising a first source;coupling a source array cross-cable with the first source; disposing thesource array cross-cable at a second depth of the body of water.
 32. Themethod of claim 31, comprising: receiving, by the at least one receiverof the first plurality of receivers, reflection data reflected off theobject in the seabed and reflected off the ocean surface during a thirdtime period, the third time period separated from the first time periodby a second intervening time period.
 33. The method of claim 31,comprising: receiving, by the at least one receiver of the firstplurality of receivers, reflection data reflected twice off the oceansurface and off the object in the seabed during a fourth time period,the fourth time period separated from the first time period by a thirdintervening time period.
 34. The method of claim 31, comprising:providing the receiver array comprising a second streamer; coupling asecond plurality of receivers with the second streamer; and receiving,by at least one receiver of the second plurality of receivers,reflection data reflected off the object in the seabed during the firsttime period and to receive reflection data reflected off the oceansurface and the object in the seabed during the second time period, thefirst time period separated from the second time period by the firstintervening time period.
 35. The method of claim 31, comprising:providing the receiver array comprising a second streamer; coupling asecond plurality of receivers with the second streamer; and receiving,by the at least one receiver of the second plurality of receiver,reflection data reflected off the object in the seabed and off the oceansurface during a third time period, the third time period separated fromthe first time period by a second intervening time period.
 36. Themethod of claim 31, comprising: providing the receiver array comprisinga second streamer; coupling a second plurality of receivers with thesecond streamer; and receiving, by the at least one receiver of thesecond plurality of receiver, reflection data reflected twice off theocean surface and off the object in the seabed during a fourth timeperiod, the fourth time period separated from the first time period by athird intervening time period.
 37. The method of claim 31, comprising:providing the first intervening time period at least 5 milliseconds. 38.The method of claim 31, comprising: providing the source array coplanarto the receiver array.
 39. The method of claim 31, comprising:receiving, by at least one receiver of the first plurality of receivers,diffraction data that includes diffracted waves originating from aseabed object and generated from a source shot.
 40. The method of claim31, comprising: towing, by a vessel, the receiver array and the sourcearray.